Tüm alıştırma soruları

188 soru

Soru 41Soru

An integer PP is given by the mathematical expression P=436203365820332892033P = 4 \cdot 36^{2033} - 6 \cdot 58^{2033} - 2 \cdot 89^{2033}. Determine the positive remainder when PP is divided by 1717.

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Cevap: 9

Cevap

9
The correct answer is derived by first reducing the bases modulo 17, giving 2, 7, and 4 respectively. Then, utilizing Fermat's Little Theorem (a161(mod17)a^{16} \equiv 1 \pmod{17}), the exponent 2033 is reduced to 2033(mod16)=12033 \pmod{16} = 1. Substituting these simplified values back into the expression yields 4(2)6(7)2(4)=424(2) - 6(7) - 2(4) = -42. Because a remainder must be positive, adding the next highest multiple of 17 (which is 17×3=5117 \times 3 = 51) to -42 gives the final valid remainder of 9.

Adım Adım Çözüm

1
Find the remainder of each base when divided by 17.
362(mod17)36 \equiv 2 \pmod{17}, 587(mod17)58 \equiv 7 \pmod{17}, and 894(mod17)89 \equiv 4 \pmod{17}.
Reducing bases before dealing with large exponents simplifies the modular arithmetic calculation.
2
Apply Fermat's Little Theorem to simplify the exponent.
Since 17 is a prime number, a161(mod17)a^{16} \equiv 1 \pmod{17}. The exponent is 2033=16×127+12033 = 16 \times 127 + 1, meaning a2033a1(mod17)a^{2033} \equiv a^1 \pmod{17}.
Fermat's Little Theorem allows us to reduce massive exponents by dividing them by (p1)(p-1) and keeping only the remainder.
3
Substitute the reduced bases and exponents into the original expression.
P4(21)6(71)2(41)(mod17)P \equiv 4(2^1) - 6(7^1) - 2(4^1) \pmod{17}, which evaluates to 8428=428 - 42 - 8 = -42.
This step calculates the combined overall remainder before adjusting for the strict definition of a positive modulo.
4
Convert the negative result to a valid positive remainder.
4242+51=9(mod17)-42 \equiv -42 + 51 = 9 \pmod{17}.
A remainder must be a non-negative integer strictly less than the divisor (17). Adding the next highest multiple of 17 (which is 51) provides the correct positive remainder.

Anahtar Kavram

Divisibility Rules and Remainder Theorem
Soru 42Soru

In a centralized database architecture, data records are distributed across 1717 server nodes numbered from 00 to 1616. A record with a numerical key KK is assigned to a node using the hash function H(K)=K(mod17)H(K) = K \pmod{17}, which always yields a positive remainder. If a specific batch of records is assigned a master key given by the expression K=220075K = 2^{200} - 75, which server node will process this batch?

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Cevap: 11

Cevap

The batch of records will be processed by server node 11.
By applying modular arithmetic rules, the expression (220075)(mod17)(2^{200} - 75) \pmod{17} simplifies individually to (17)=6(1 - 7) = -6. Because node numbers in this system must be positive, adding the divisor 17 to -6 provides the correct positive remainder, which is 11.

Adım Adım Çözüm

1
Identify the mathematical goal of the problem.
Calculate (220075)(mod17)(2^{200} - 75) \pmod{17} and ensure the final result is a positive integer between 0 and 16.
The server nodes are assigned strictly based on the positive remainder when the key is divided by 17.
2
Find the remainder of the exponential term 22002^{200} divided by 17.
24=161(mod17)2^4 = 16 \equiv -1 \pmod{17}. Raising this to the 50th power gives (24)50(1)50=1(mod17)(2^4)^{50} \equiv (-1)^{50} = 1 \pmod{17}.
Finding a power of the base that is 1 or -1 modulo the divisor simplifies extremely large exponent calculations.
3
Find the remainder of the constant term 75 divided by 17.
75=17×4+775 = 17 \times 4 + 7, so 757(mod17)75 \equiv 7 \pmod{17}.
Each term in a modular arithmetic expression can and should be reduced individually.
4
Combine the reduced terms to find the overall remainder.
17=6(mod17)1 - 7 = -6 \pmod{17}.
Substitute the individual reduced remainders back into the original expression K=220075K = 2^{200} - 75.
5
Convert the negative remainder into a valid positive node number.
6+17=11-6 + 17 = 11.
A remainder of -6 indicates the value is 6 units short of a full multiple of 17. The equivalent positive remainder is found by adding the divisor.

Anahtar Kavram

Modular arithmetic with large exponents and handling negative remainders appropriately.
Tahmini Süre:1m 30s
Soru 43Soru

Calculate the remainder when the integer value of 11×177311 \times 17^{73} is divided by 1919.

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Cevap: 16

Cevap

16
The correct remainder is found by applying Fermat's Little Theorem to reduce the large exponent, yielding an intermediate calculation of -22. Converting this negative value to a proper positive remainder modulo 19 gives exactly 16.

Adım Adım Çözüm

1
Simplify the base of the exponent modulo 19.
172(mod19)17 \equiv -2 \pmod{19}
Working with a smaller absolute value simplifies subsequent exponentiation steps.
2
Apply Fermat's Little Theorem to identify the cyclicity.
a181(mod19)a^{18} \equiv 1 \pmod{19} for any integer aa not divisible by 19.
Since 19 is a prime number, the remainders of powers will repeat in cycles of 18.
3
Reduce the large exponent 7373 using the identified cyclicity.
73=18×4+173 = 18 \times 4 + 1, which means (2)73(2)1(mod19)(-2)^{73} \equiv (-2)^1 \pmod{19}
Because the powers cycle every 18, only the remainder of the exponent divided by 18 affects the final result.
4
Multiply the reduced exponential term by the leading coefficient.
11×(2)=2211 \times (-2) = -22
The original mathematical expression contains a coefficient of 11.
5
Convert the negative intermediate result to a valid positive remainder.
2222+2×19=22+38=16(mod19)-22 \equiv -22 + 2 \times 19 = -22 + 38 = 16 \pmod{19}
By standard definition, a remainder must be a positive integer strictly less than the divisor.

Anahtar Kavram

Modular Arithmetic and Fermat's Little Theorem
Soru 44Soru

A logistics manager is arranging shipping containers into equal stacks. When the containers are stacked in groups of 1818, 2424, or 3232, there are always exactly 1111 containers left over. However, when they are stacked in groups of 3535, there are no containers left over. What is the minimum total number of containers the manager could have?

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Cevap: 875

Cevap

875
The correct answer is derived by recognizing that the total number of containers must take the form of LCM(18,24,32)×k+11LCM(18, 24, 32) \times k + 11. The LCM is 288288, so the number is 288k+11288k + 11. We then find the smallest integer kk such that (288k+11)(288k + 11) is perfectly divisible by 3535. By evaluating the expression for sequential values of kk (or using modular arithmetic, 8k24(mod35)8k \equiv 24 \pmod{35}), we find that k=3k = 3 is the smallest valid multiplier. Substituting this back yields 288(3)+11=875288(3) + 11 = 875.

Adım Adım Çözüm

1
Calculate the Least Common Multiple (LCM) of the initial stack group sizes (1818, 2424, and 3232).
The prime factorizations are 18=2×3218 = 2 \times 3^2, 24=23×324 = 2^3 \times 3, and 32=2532 = 2^5. The LCM is 25×32=32×9=2882^5 \times 3^2 = 32 \times 9 = 288.
The base cycle for the stacks without remainders requires finding the smallest number perfectly divisible by all three group sizes.
2
Express the total number of containers algebraically.
Let the total number of containers be NN. We can write N=288k+11N = 288k + 11, where kk is a positive integer.
Since there is always a remainder of 1111 containers when divided by these numbers, the total must be 1111 more than a multiple of their LCM.
3
Apply the secondary divisibility condition.
The problem states that NN is exactly divisible by 3535. Therefore, 288k+110(mod35)288k + 11 \equiv 0 \pmod{35}.
When the containers are grouped by 3535, there is no remainder.
4
Solve the congruence to find the smallest integer kk.
First, simplify 288(mod35)288 \pmod{35}: since 35×8=28035 \times 8 = 280, we have 2888(mod35)288 \equiv 8 \pmod{35}. The equation becomes 8k+110(mod35)8k + 11 \equiv 0 \pmod{35}, or 8k1124(mod35)8k \equiv -11 \equiv 24 \pmod{35}. Dividing both sides by 88 gives k=3k = 3.
Finding the smallest valid positive integer kk will yield the minimum total number of containers.
5
Calculate the final number of containers using k=3k = 3.
N=288(3)+11=864+11=875N = 288(3) + 11 = 864 + 11 = 875.
Substitute the multiplier back into the original algebraic expression.

Anahtar Kavram

Solving for an unknown quantity using the Least Common Multiple (LCM) combined with constant remainder logic and a secondary divisibility condition.

Alternatif Yöntem

Instead of using modular arithmetic to solve 288k+110(mod35)288k + 11 \equiv 0 \pmod{35}, you can manually test integer values for kk in the formula N=288k+11N = 288k + 11. For k=1k=1, N=288(1)+11=299N = 288(1) + 11 = 299 (299÷35299 \div 35 leaves remainder 1919). For k=2k=2, N=288(2)+11=587N = 288(2) + 11 = 587 (587÷35587 \div 35 leaves remainder 2727). For k=3k=3, N=288(3)+11=875N = 288(3) + 11 = 875 (875÷35=25875 \div 35 = 25 with no remainder). Therefore, 875875 is the smallest valid number.
Tahmini Süre:2m 30s
Soru 45Soru

A solar energy farm has a continuous linear array of 105105 solar panels. Panel Sigma is currently positioned 43rd43^{\text{rd}} from the left end of the array. Due to a localized upgrade project, the first 1818 panels from the left end and the last 2424 panels from the right end are temporarily removed from the array. In the newly formed, shorter array of remaining panels, what is the position of Panel Sigma from the right end?

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Cevap: 39

Cevap

39
Panel Sigma's original position from the left is 43rd43^{\text{rd}}. When 1818 panels are removed from the front, its new position from the left becomes 4318=25th43 - 18 = 25^{\text{th}}. The initial total was 105105 panels. After removing 1818 from the left and 2424 from the right, the new total is 1051824=63105 - 18 - 24 = 63 panels. Using the standard ranking formula (Total=Left+Right1Total = Left + Right - 1), the position from the right is calculated as 6325+1=39th63 - 25 + 1 = 39^{\text{th}}.

Adım Adım Çözüm

1
Calculate the new total number of panels in the array.
1051824=63105 - 18 - 24 = 63 panels
Removing panels from both ends reduces the overall length of the array.
2
Determine Panel Sigma's new position from the left end.
4318=25th43 - 18 = 25^{\text{th}} from the left
Removing 18 panels from the left shifts Panel Sigma 18 positions closer to the left end.
3
Calculate Panel Sigma's new position from the right end.
Position from right = 6325+1=39th63 - 25 + 1 = 39^{\text{th}}
Using the standard ranking formula (Total = Left Position + Right Position - 1), we find the right-side position.

Anahtar Kavram

Positional shift and total rank calculation in a truncated linear arrangement

Alternatif Yöntem

Instead of calculating the new total, you can determine how many panels are strictly to the right of Panel Sigma. Initially, there are 10543=62105 - 43 = 62 panels to its right. Removing 2424 panels from the right end leaves 6224=3862 - 24 = 38 panels to its right. Since there are 3838 panels after it, Panel Sigma must be the 39th39^{\text{th}} panel from the right end.
Tahmini Süre:1m 0s
Soru 46Soru

In a processing queue of a mainframe computer, Job Alpha is positioned 28th28^{\text{th}} from the front of the queue, and Job Beta is positioned 34th34^{\text{th}} from the back of the queue. If there are exactly 1212 jobs currently waiting between Job Alpha and Job Beta, what is the minimum possible total number of jobs in this queue?

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Cevap: 48

Cevap

48
To find the minimum possible number of jobs, we assume an overlapping sequence. The formula for the minimum total in a ranking problem is: Total = (Rank from Front) + (Rank from Back) - (Number of items in between) - 2. Substituting the values gives: 28 + 34 - 12 - 2 = 62 - 14 = 48.

Adım Adım Çözüm

1
Identify the queue configuration required for a minimum total.
The configuration must be overlapping, meaning Job Beta is ahead of Job Alpha in the queue.
An overlapping configuration results in the smallest possible total number of items because the counted items from both ends overlap.
2
Apply the minimum total formula for overlapping cases.
Total = Rank of Alpha from front + Rank of Beta from back - Jobs between them - 2
This formula deducts the overlapping region (the jobs between them and the two jobs themselves) which were counted twice.
3
Substitute the provided numerical values into the formula.
Total = 28 + 34 - 12 - 2
Job Alpha is 28th, Job Beta is 34th, and there are 12 jobs in between.
4
Calculate the final value.
Total = 62 - 14 = 48
Basic arithmetic yields the minimum possible number of jobs in the queue.

Anahtar Kavram

Order and Ranking (Overlapping/Minimum Capacity Queue)
Soru 47Soru

Four navigation buoys in a harbor flash at regular intervals of 3133 \frac{1}{3} minutes, 4164 \frac{1}{6} minutes, 5595 \frac{5}{9} minutes, and 7127 \frac{1}{2} minutes, respectively. If all four buoys flash simultaneously at exactly 12:00 noon, how many additional times will they all flash together again within the next 1212 hours?

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Cevap: 4

Cevap

4
The correct answer is derived by finding the Least Common Multiple of the fractional intervals to determine the duration between simultaneous flashes (150 minutes). Then, by converting the 12-hour period into 720 minutes, dividing 720 by 150 yields 4.8, indicating the buoys will flash together 4 additional times within that exact timeframe.

Adım Adım Çözüm

1
Convert the mixed numbers into improper fractions.
The intervals are 103\frac{10}{3}, 256\frac{25}{6}, 509\frac{50}{9}, and 152\frac{15}{2} minutes.
Mathematical operations involving LCM and HCF of fractions require them to be in proper or improper fractional forms, rather than mixed numbers.
2
Determine the mathematical formula required for simultaneous events.
We must calculate the Least Common Multiple (LCM) of the intervals using the formula: LCM of fractions=LCM of numeratorsHCF of denominators\text{LCM of fractions} = \frac{\text{LCM of numerators}}{\text{HCF of denominators}}.
Simultaneous cyclic events synchronize at the lowest common multiple of their individual intervals.
3
Calculate the LCM of the numerators.
The numerators are 10,25,5010, 25, 50, and 1515. Their LCM is 150150.
150150 is the smallest integer divisible by all four numerators (150=10×15=25×6=50×3=15×10150 = 10 \times 15 = 25 \times 6 = 50 \times 3 = 15 \times 10).
4
Calculate the HCF of the denominators.
The denominators are 3,6,93, 6, 9, and 22. Their HCF is 11.
The numbers 22 and 33 are coprime (they share no common factors greater than 11), forcing the overall HCF of the set to be 11.
5
Calculate the exact time interval between simultaneous flashes.
The LCM of the intervals is 1501=150\frac{150}{1} = 150 minutes.
Applying the results from steps 3 and 4 directly into the fractional LCM formula.
6
Determine how many times this 150-minute interval fits into the 12-hour window.
12 hours=720 minutes12 \text{ hours} = 720 \text{ minutes}. 720150=4.8=4\lfloor \frac{720}{150} \rfloor = \lfloor 4.8 \rfloor = 4.
Dividing the total available time by the simultaneous interval length gives the exact count of additional flashes.

Anahtar Kavram

LCM of fractions in simultaneous cyclic events
Soru 48Soru

Evaluate the remainder when the numeric expression 47101+1111012547^{101} + 111^{101} - 25 is divided by 1616.

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Cevap: 5

Cevap

5
By applying the properties of modular arithmetic, we determine that 471(mod16)47 \equiv -1 \pmod{16} and 1111(mod16)111 \equiv -1 \pmod{16}. Raising these to the 101st power yields 1-1 and 1-1. Subtracting 25 gives a total of 27-27. To find the positive remainder, we add the next highest multiple of 16 (which is 32) to -27, yielding a final valid positive remainder of 5.

Adım Adım Çözüm

1
Find the remainder of the bases when divided by 16.
471(mod16)47 \equiv -1 \pmod{16} and 1111(mod16)111 \equiv -1 \pmod{16}.
Using negative remainders (since 47=16×3147 = 16 \times 3 - 1 and 111=16×71111 = 16 \times 7 - 1) significantly simplifies the calculation of large powers.
2
Substitute the simplified bases into the original expression.
(47)101+(111)10125(1)101+(1)10125(mod16)(47)^{101} + (111)^{101} - 25 \equiv (-1)^{101} + (-1)^{101} - 25 \pmod{16}.
The properties of modular arithmetic allow replacing bases with their congruent values modulo the divisor.
3
Evaluate the exponents and the constant term.
(1)+(1)25=27(-1) + (-1) - 25 = -27.
An odd power of a negative number remains negative, so (1)101=1(-1)^{101} = -1.
4
Find the equivalent positive remainder for -27 modulo 16.
275(mod16)-27 \equiv 5 \pmod{16}.
Adding multiples of 16 (in this case, 16×2=3216 \times 2 = 32) to 27-27 yields a positive remainder in the valid range of 00 to 1515. Calculating 27+32=5-27 + 32 = 5 gives the final remainder.

Anahtar Kavram

Modular arithmetic with large powers using negative remainders

Alternatif Yöntem

Instead of converting the bases to -1, one could convert them to positive 15. The expression becomes 15101+151012515^{101} + 15^{101} - 25. However, evaluating this requires recognizing that 151(mod16)15 \equiv -1 \pmod{16} to easily compute the large exponents, which ultimately merges back into the primary solution path.
Tahmini Süre:1m 30s
Soru 49Soru

A digital encryption protocol derives a validation key from the mathematical properties of the integer 1260012600. The key is calculated by multiplying the total quantity of its even positive divisors by the total quantity of its odd positive divisors. What is the exact value of this validation key?

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Cevap: 972

Cevap

972
By finding the prime factorization of 1260012600 as 23×32×52×712^3 \times 3^2 \times 5^2 \times 7^1, we can separate the divisors into even and odd categories. Odd divisors utilize only the odd prime factors, yielding a total of (2+1)(2+1)(1+1)=18(2+1)(2+1)(1+1) = 18 odd divisors. Even divisors require at least one power of 22, giving 3×(2+1)(2+1)(1+1)=543 \times (2+1)(2+1)(1+1) = 54 even divisors. Following the protocol's rule, their product is 18×54=97218 \times 54 = 972.

Adım Adım Çözüm

1
Find the prime factorization of 1260012600.
12600=23×32×52×7112600 = 2^3 \times 3^2 \times 5^2 \times 7^1
Prime factorization is necessary to determine the number and types of divisors an integer has.
2
Calculate the quantity of odd positive divisors.
Number of odd divisors = 1818
Odd divisors are formed by using only the odd prime factors (33, 55, and 77). By adding 11 to each of their exponents and multiplying them, we get (2+1)×(2+1)×(1+1)=3×3×2=18(2+1) \times (2+1) \times (1+1) = 3 \times 3 \times 2 = 18.
3
Calculate the quantity of even positive divisors.
Number of even divisors = 5454
Even divisors must include at least one factor of 22. The number of choices for the power of 22 is equal to its exponent (33 choices: 21,22,232^1, 2^2, 2^3). Multiplying this by the choices for odd prime factors gives 3×(2+1)×(2+1)×(1+1)=3×3×3×2=543 \times (2+1) \times (2+1) \times (1+1) = 3 \times 3 \times 3 \times 2 = 54.
4
Multiply the number of even divisors by the number of odd divisors to find the validation key.
54×18=97254 \times 18 = 972
The encryption protocol specifically defines the key as the product of these two calculated quantities.

Anahtar Kavram

Prime Factorization and Number of Divisors (Even and Odd)
Soru 50Soru

A large solid cube of side length 6 cm6 \text{ cm} has its opposite faces painted with the same color. The colors used are red, blue, and yellow. After the paint dries, the large cube is completely cut into smaller cubes of side length 1 cm1 \text{ cm} each. How many of these smaller cubes will have exactly two faces painted, with one face being red and the other face being yellow?

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Cevap: 16

Cevap

16 cubes
There are exactly 4 edges where a red face and a yellow face meet. Each of these edges contains exactly 4 middle cubes (excluding the corner cubes) that have exactly two faces painted. Therefore, multiplying 4 edges×4 cubes4 \text{ edges} \times 4 \text{ cubes} gives 16.

Adım Adım Çözüm

1
Calculate the number of smaller cubes along one edge of the large cube.
n=6/1=6n = 6 / 1 = 6 cubes per edge.
The value nn is required to determine how many cubes lie along any given dimension.
2
Determine the number of edges where a red face and a yellow face intersect.
There are exactly 4 intersecting edges.
The cube has 2 red faces (top/bottom) and 2 yellow faces (left/right). Each of the 2 red faces meets both of the 2 yellow faces, resulting in 2×2=42 \times 2 = 4 edges.
3
Calculate how many cubes on a single edge have exactly two faces painted.
n2=62=4n - 2 = 6 - 2 = 4 cubes per edge.
The cubes at the two extreme ends of any edge are corner cubes with three painted faces, so they must be subtracted from the total edge length.
4
Multiply the number of relevant edges by the number of two-face painted cubes per edge.
4 edges×4 cubes=164 \text{ edges} \times 4 \text{ cubes} = 16 cubes.
This yields the total count of smaller cubes possessing exactly one red and one yellow painted face.

Anahtar Kavram

Calculation of painted smaller cubes resulting from cutting a colored larger cube based on intersecting faces.
Soru 51Soru

A computer algorithm processes a data block and assigns it a routing ID based on modular arithmetic. This ID corresponds to the strictly positive remainder left after dividing the value of 561034556^{103} - 45 by 1313.

Find the value of this routing ID.

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Cevap: 11

Cevap

11
By reducing each component of the expression modulo 13, 5610356^{103} reduces to 41034^{103}, which simplifies to 44 because 431(mod13)4^3 \equiv -1 \pmod{13}. Subtracting 45(mod13)45 \pmod{13}, which is 66, yields 2-2. Adding the divisor 13 to 2-2 gives the strictly positive remainder of 11.

Adım Adım Çözüm

1
Reduce the base 56 modulo 13.
564(mod13)56 \equiv 4 \pmod{13}
Modular arithmetic allows simplifying the base before exponentiation.
2
Find a pattern to easily evaluate 4103(mod13)4^{103} \pmod{13}.
43=641(mod13)4^3 = 64 \equiv -1 \pmod{13}
Finding a small power that is congruent to 1 or -1 simplifies large exponents significantly.
3
Evaluate 4103(mod13)4^{103} \pmod{13} using the established pattern.
4103=(43)34×41(1)34×4=4(mod13)4^{103} = (4^3)^{34} \times 4^1 \equiv (-1)^{34} \times 4 = 4 \pmod{13}
Exponent rules allow breaking down 103 into 3×34+13 \times 34 + 1.
4
Reduce the subtracted constant 45 modulo 13.
45=13×3+66(mod13)45 = 13 \times 3 + 6 \equiv 6 \pmod{13}
All terms in the expression must be evaluated under the same modulus.
5
Subtract the reduced values.
46=24 - 6 = -2
Substitute the individual modulo results back into the original expression structure.
6
Convert the negative remainder into a positive remainder.
2+13=11-2 + 13 = 11
The question asks for a strictly positive remainder, which is standard in modular division contexts.

Anahtar Kavram

Modular Arithmetic and Negative Remainders
Soru 52Soru

In a technology seminar attended by 6060 software engineers, 3535 engineers know Python and 2525 engineers know Java. If 1010 engineers know both Python and Java, how many engineers know neither of these two programming languages?

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Cevap: 10

Cevap

The number of engineers who know neither Python nor Java is 10.
The correct answer is 10. By taking the sum of Python knowers (3535) and Java knowers (2525) and subtracting those who know both (1010), we obtain 5050 engineers who know at least one language. Subtracting this from the total 6060 seminar participants leaves 1010 engineers who know neither language.

Adım Adım Çözüm

1
Find the total number of engineers who know at least one programming language
50 engineers know at least one language
Apply the two-set union formula: n(AB)=n(A)+n(B)n(AB)=35+2510=50n(A \cup B) = n(A) + n(B) - n(A \cap B) = 35 + 25 - 10 = 50.
2
Calculate the number of engineers who know neither language
10 engineers know neither language
Subtract the number of engineers knowing at least one language from the total group size: 6050=1060 - 50 = 10.

Anahtar Kavram

Two-Set Inclusion-Exclusion Principle and Complement of Sets
Soru 53Soru

An archaeological surveyor starting from a central benchmark walks 20 m20\text{ m} due East. He then turns 135135^\circ to his left and walks 142 m14\sqrt{2}\text{ m}. Next, he turns 4545^\circ to his left and walks 18 m18\text{ m}. Finally, he turns 9090^\circ to his right and walks 2 m2\text{ m} to reach an excavation site. What is the shortest direct distance (in meters) between the starting benchmark and the excavation site?

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Cevap: 20

Cevap

The shortest direct distance between the starting benchmark and the excavation site is 20 meters.
By resolving each sequential movement into Cartesian coordinate components (x,y)(x, y), the final position relative to origin (0,0)(0,0) is found to be (12 m,16 m)(-12\text{ m}, 16\text{ m}). The straight-line distance is computed using the distance formula (12)2+(16)2=144+256=400=20 m\sqrt{(-12)^2 + (16)^2} = \sqrt{144 + 256} = \sqrt{400} = 20\text{ m}.

Adım Adım Çözüm

1
Plot the initial displacement on a Cartesian coordinate plane with origin (0,0)(0,0) at the starting benchmark.
Position after walking 20 m20\text{ m} East is (20,0)(20, 0) facing East (00^\circ).
East represents the positive x-axis direction.
2
Calculate displacement after turning 135135^\circ left (facing North-West) and walking 142 m14\sqrt{2}\text{ m}.
Position becomes (2014,0+14)=(6,14)(20 - 14, 0 + 14) = (6, 14).
In North-West direction, horizontal component is 142×12=14 m-14\sqrt{2} \times \frac{1}{\sqrt{2}} = -14\text{ m} and vertical component is +142×12=+14 m+14\sqrt{2} \times \frac{1}{\sqrt{2}} = +14\text{ m}.
3
Calculate displacement after turning 4545^\circ left from North-West (facing West) and walking 18 m18\text{ m}.
Position becomes (618,14)=(12,14)(6 - 18, 14) = (-12, 14).
Turning 4545^\circ left from North-West aligns facing direction with West (negative x-axis).
4
Calculate displacement after turning 9090^\circ right from West (facing North) and walking 2 m2\text{ m}.
Final position is (12,14+2)=(12,16)(-12, 14 + 2) = (-12, 16).
Turning 9090^\circ right from West aligns facing direction with North (positive y-axis).
5
Calculate the direct straight-line distance from starting point (0,0)(0,0) to final position (12,16)(-12, 16).
Distance D=(12)2+162=144+256=400=20 mD = \sqrt{(-12)^2 + 16^2} = \sqrt{144 + 256} = \sqrt{400} = 20\text{ m}.
Applying the Pythagorean theorem D=x2+y2D = \sqrt{x^2 + y^2} yields the shortest distance.

Anahtar Kavram

Coordinate Geometry and Vector Resolution in Direction and Distance Problems
Tahmini Süre:2m 0s
Soru 54Soru

Analyze the pattern in the numerical sequence given below:

4,9,20,43,90,?4, \quad 9, \quad 20, \quad 43, \quad 90, \quad ?

What is the value of the missing term that completes the sequence?

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Cevap: 185

Cevap

185
Each consecutive term is calculated by doubling the previous term and adding an increasing integer (+1,+2,+3,+4,+5+1, +2, +3, +4, +5). Following this rule, 90×2+5=18590 \times 2 + 5 = 185.

Adım Adım Çözüm

1
Examine differences or operations between adjacent terms
94=59 - 4 = 5, 209=1120 - 9 = 11, 4320=2343 - 20 = 23, 9043=4790 - 43 = 47
Identify the primary numerical increment pattern
2
Analyze the rule for term progression
The operations follow Tn=Tn1×2+(n1)T_n = T_{n-1} \times 2 + (n-1) for n2n \ge 2
Confirm consistency across all given terms
3
Compute the sixth term (T6T_6)
T6=90×2+5=185T_6 = 90 \times 2 + 5 = 185
Apply the addition increment +5+5 following +4+4

Anahtar Kavram

Number and Alphabet Series
Soru 55Soru

A wholesale merchant has three batches of specialty syrups measuring 635\frac{63}{5} liters, 7225\frac{72}{25} liters, and 8110\frac{81}{10} liters in volume. To distribute them in uniform sample sizes, the merchant wants to repackage all the syrup into identical smaller bottles filled exactly to the brim, ensuring no syrup is left over from any of the original batches. What is the maximum possible capacity (in liters) of each sample bottle?

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Cevap: 0.18

Cevap

The maximum possible capacity of each sample bottle is 0.18 liters.
To find the maximum capacity of uniform bottles that can hold the syrup from any batch without leftover, we must find the Highest Common Factor (HCF) of the respective volumes. For fractions, the rule is HCF=HCF of numeratorsLCM of denominators\text{HCF} = \frac{\text{HCF of numerators}}{\text{LCM of denominators}}. The HCF of the numerators (63,72,8163, 72, 81) is 99, and the LCM of the denominators (5,25,105, 25, 10) is 5050. The resulting maximum capacity is 950\frac{9}{50}, which equals 0.180.18 liters.

Adım Adım Çözüm

1
Determine the mathematical operation required.
Calculate the HCF of 635\frac{63}{5}, 7225\frac{72}{25}, and 8110\frac{81}{10}.
Finding the largest equal container size that leaves no remainder requires computing the Highest Common Factor.
2
Apply the rule for finding the HCF of fractions.
HCF of fractions=HCF of numeratorsLCM of denominators\text{HCF of fractions} = \frac{\text{HCF of numerators}}{\text{LCM of denominators}}
This standard formula correctly identifies the greatest common divisor for a set of rational numbers.
3
Find the HCF of the numerators.
HCF(63,72,81)=9\text{HCF}(63, 72, 81) = 9
The largest integer that perfectly divides 63, 72, and 81 is 9.
4
Find the LCM of the denominators.
LCM(5,25,10)=50\text{LCM}(5, 25, 10) = 50
The smallest integer that is a multiple of 5, 25, and 10 is 50.
5
Compute the final fraction and convert it to a decimal.
950=0.18\frac{9}{50} = 0.18
Dividing the HCF of the numerators by the LCM of the denominators yields the exact capacity in liters.

Anahtar Kavram

HCF and LCM of fractions
Soru 56Soru

A local water reservoir was initially filled to exactly 0.30.\overline{3} of its maximum capacity. After several days of heavy rainfall, an additional 14.414.4 million liters of water flowed into the reservoir, bringing the water level to 0.60.6 of its maximum capacity.

Currently, a nearby town consumes water from the reservoir at a steady rate of 1121\frac{1}{2} million liters per day. Additionally, an undiscovered leak at the base of the reservoir drains water at a constant rate of 0.050.05 million liters per hour.

If the reservoir were completely full and no further water was added, in how many days would it become completely empty?

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Cevap: 20

Cevap

20
The total capacity of the reservoir is found by equating the fractional increase (3513=415\frac{3}{5} - \frac{1}{3} = \frac{4}{15}) to the volume added (14.414.4 million liters), yielding 5454 million liters. The total daily water depletion is the sum of the town's daily usage (1.51.5 million liters) and the leak converted to a daily rate (0.05×24=1.20.05 \times 24 = 1.2 million liters), giving 2.72.7 million liters per day. Dividing 5454 by 2.72.7 gives exactly 2020 days.

Adım Adım Çözüm

1
Convert the decimal fill levels into fractions and compute their difference.
Initial level = 13\frac{1}{3}. Final level = 35\frac{3}{5}. Difference = 3513=415\frac{3}{5} - \frac{1}{3} = \frac{4}{15}.
Working with exact fractions avoids rounding errors from recurring decimals and simplifies finding the proportion of water added.
2
Calculate the maximum capacity of the reservoir.
415×Capacity=14.4    Capacity=14.4×154=54\frac{4}{15} \times \text{Capacity} = 14.4 \implies \text{Capacity} = 14.4 \times \frac{15}{4} = 54 million liters.
The difference in the fractional water level represents exactly the volume of rain added.
3
Calculate the total volume of water lost per day.
Town = 1.51.5 million L/day. Leak = 0.05×24=1.20.05 \times 24 = 1.2 million L/day. Total = 2.72.7 million L/day.
The rates must be in the same time unit (days) before they can be accurately combined.
4
Determine the time required to empty the completely full reservoir.
54÷2.7=2054 \div 2.7 = 20 days.
Dividing the total capacity by the combined daily rate of depletion gives the time in days.

Anahtar Kavram

Fractions and Decimals
Tahmini Süre:3m 0s
Soru 57Soru

In a regional agricultural department, a survey was conducted among 160160 field officers regarding their supervisory duties across three major crop initiatives: Wheat (WW), Rice (RR), and Cotton (CC). The survey revealed that 8585 officers supervise Wheat, 7070 supervise Rice, and 6060 supervise Cotton. Furthermore, 3535 officers supervise both Wheat and Rice, 2525 supervise both Rice and Cotton, 3030 supervise both Wheat and Cotton, and 1515 officers supervise all three crop initiatives. How many field officers supervise exactly two of these three crop initiatives?

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Cevap: 45

Cevap

The total number of field officers who supervise exactly two crop initiatives is 45.
To find the number of officers supervising exactly two crop initiatives, we calculate the number of officers in each pair of overlapping sets exclusive of the three-set intersection: for Wheat and Rice only (3515=2035 - 15 = 20), for Rice and Cotton only (2515=1025 - 15 = 10), and for Wheat and Cotton only (3015=1530 - 15 = 15). Summing these three regions gives 20+10+15=4520 + 10 + 15 = 45.

Adım Adım Çözüm

1
Extract intersection values for each pair of sets and subtract the central intersection of all three sets
Only Wheat and Rice = 3515=2035 - 15 = 20; Only Rice and Cotton = 2515=1025 - 15 = 10; Only Wheat and Cotton = 3015=1530 - 15 = 15
The given pairwise intersections include officers who supervise all three initiatives. To isolate those who supervise exactly two, the three-set intersection must be removed from each pairwise intersection.
2
Sum the three distinct 'exactly two' regions
Total = 20+10+15=4520 + 10 + 15 = 45
Adding these disjoint counts yields the total number of officers supervising precisely two crop initiatives.

Anahtar Kavram

Inclusion-Exclusion Principle and Venn Diagram Region Analysis for Three Overlapping Sets
Soru 58Soru

In a class merit list, Rahul is ranked 15th15^{\text{th}} from the top and 21st21^{\text{st}} from the bottom. What is the total number of students in the class?

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Cevap: 35

Cevap

The total number of students in the class is 3535.
When the position of a single person is given from both ends of a line, the total count is calculated using the formula Total=Position from Left/Top+Position from Right/Bottom1\text{Total} = \text{Position from Left/Top} + \text{Position from Right/Bottom} - 1. Substituting the values gives 15+211=3515 + 21 - 1 = 35.

Adım Adım Çözüm

1
Identify the given ranks from both ends for the same person.
Rank from top = 15, Rank from bottom = 21.
The position of Rahul is provided relative to both the start and end of the queue.
2
Apply the single-person dual rank total calculation formula.
Total=Ranktop+Rankbottom1\text{Total} = \text{Rank}_{\text{top}} + \text{Rank}_{\text{bottom}} - 1
Since Rahul is included in both rank counts, adding the ranks counts him twice, requiring a subtraction of 1.
3
Perform the computation.
15+211=3515 + 21 - 1 = 35
Simplifying the arithmetic yields the exact total headcount of the class.

Anahtar Kavram

Single-Person Dual Rank Total Calculation
Soru 59Soru

In a district administration department, a survey was conducted among 250250 officers regarding their technical expertise in three digital governance domains: Cyber Security (CC), Data Analytics (DD), and Public Grievance Portals (PP). The data collected is as follows:
- 120120 officers have expertise in Data Analytics.
- 115115 officers have expertise in Cyber Security.
- 100100 officers have expertise in Public Grievance Portals.
- 5050 officers have expertise in both Data Analytics and Cyber Security.
- 4545 officers have expertise in both Cyber Security and Public Grievance Portals.
- 4040 officers have expertise in both Data Analytics and Public Grievance Portals.
- 2020 officers possess expertise in all three digital governance domains.

Based on the given data, how many officers have expertise in EXACTLY TWO of these three domains?

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Cevap: 75

Cevap

The total number of officers who have expertise in exactly two digital governance domains is 75.
To find the number of officers with expertise in exactly two domains, we calculate the exclusive intersection regions by subtracting the central three-set intersection (2020) from each of the given double-intersection totals: (5020)+(4520)+(4020)=30+25+20=75(50 - 20) + (45 - 20) + (40 - 20) = 30 + 25 + 20 = 75.

Adım Adım Çözüm

1
Calculate the number of officers in the region representing expertise in ONLY Data Analytics and Cyber Security
5020=3050 - 20 = 30 officers
The total intersection of Data Analytics and Cyber Security includes officers proficient in all three domains. Subtracting the 3-domain count isolates those proficient in only these two.
2
Calculate the number of officers in the region representing expertise in ONLY Cyber Security and Public Grievance Portals
4520=2545 - 20 = 25 officers
Subtracting the 3-domain count from the total intersection of Cyber Security and Public Grievance Portals isolates those proficient in only these two.
3
Calculate the number of officers in the region representing expertise in ONLY Data Analytics and Public Grievance Portals
4020=2040 - 20 = 20 officers
Subtracting the 3-domain count from the total intersection of Data Analytics and Public Grievance Portals isolates those proficient in only these two.
4
Sum the three mutually exclusive regions representing expertise in exactly two domains
30+25+20=7530 + 25 + 20 = 75 officers
Adding these disjoint sets yields the total number of officers with expertise in exactly two of the three digital governance domains.

Anahtar Kavram

Principle of Inclusion-Exclusion and Venn Diagram Region Partitioning
Tahmini Süre:2m 0s
Soru 60Soru

In a published civil services merit list, Rohan is ranked 14th14^{\text{th}} from the top, while Seema is ranked 33rd33^{\text{rd}} from the bottom. After a re-evaluation of marks, Rohan and Seema interchange their positions, resulting in Rohan becoming 48th48^{\text{th}} from the top. A third candidate, Amit, holds a rank exactly halfway between Rohan's new position and Seema's new position. If 66 candidates ranked above Amit withdraw their candidature and 44 new candidates are placed below Amit in the updated list, what is Amit's final rank from the bottom of the modified merit list?

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Cevap: 54

Cevap

Amit's final rank from the bottom of the modified merit list is 54.
Seema's dual information (48th48^{\text{th}} from top and 33rd33^{\text{rd}} from bottom) gives an initial total of 80 candidates. Amit's midpoint position between 14th14^{\text{th}} and 48th48^{\text{th}} is 31st31^{\text{st}} from top, placing 49 candidates below him. Accounting for 6 withdrawals above and 4 additions below leaves 53 candidates below Amit, establishing his final rank as 54th54^{\text{th}} from the bottom.

Adım Adım Çözüm

1
Find total candidates in the original merit list using the interchange data.
Total candidates N = 80
When Rohan and Seema interchange positions, Rohan occupies Seema's original spot (48th48^{\text{th}} from top). Since Seema was 33rd33^{\text{rd}} from bottom, N=48+331=80N = 48 + 33 - 1 = 80.
2
Calculate Amit's initial rank from the top.
Amit's initial top rank = 31st
Amit is positioned halfway between Seema's new position (14th14^{\text{th}} from top) and Rohan's new position (48th48^{\text{th}} from top), so rank = (14+48)/2=31st(14 + 48) / 2 = 31^{\text{st}}.
3
Find initial counts of candidates ranked above and below Amit.
30 candidates above, 49 candidates below
With a top rank of 31st31^{\text{st}} out of 80, there are 311=3031 - 1 = 30 candidates above Amit and 8031=4980 - 31 = 49 candidates below Amit.
4
Adjust counts based on candidate withdrawals and additions.
24 candidates above, 53 candidates below
Subtract 6 from candidates above (306=2430 - 6 = 24) and add 4 to candidates below (49+4=5349 + 4 = 53).
5
Calculate Amit's revised rank from the bottom.
54th from the bottom
The rank from the bottom equals (candidates below + 1), which gives 53+1=5453 + 1 = 54.

Anahtar Kavram

Dual Rank Position Interchange, Midpoint Computation, and Dynamic List Adjustment
Tahmini Süre:2m 30s
ÖncekiSayfa 3 / 10Sonraki
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