Tüm alıştırma soruları

5215 soru

Soru 2101Soru →

Pair the given polynomial expressions on the left with their fully factored equivalents on the right.

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Öğeler

4x2−254x^2 - 25
x2−8x+15x^2 - 8x + 15
3x2+12x−153x^2 + 12x - 15
2x3−8x2x^3 - 8x

Eşleşmeler

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Cevap

The correct pairings are: 4x2−254x^2 - 25 with (2x−5)(2x+5)(2x - 5)(2x + 5); x2−8x+15x^2 - 8x + 15 with (x−3)(x−5)(x - 3)(x - 5); 3x2+12x−153x^2 + 12x - 15 with 3(x+5)(x−1)3(x + 5)(x - 1); and 2x3−8x2x^3 - 8x with 2x(x−2)(x+2)2x(x - 2)(x + 2).
Each polynomial expression was broken down into its fundamental algebraic components by identifying patterns such as the difference of squares, standard trinomial factoring, and extracting the greatest common factor.

Adım Adım Çözüm

1
Analyze the first expression 4x2−254x^2 - 25.
It factors to (2x−5)(2x+5)(2x - 5)(2x + 5).
It follows the difference of squares pattern a2−b2=(a−b)(a+b)a^2 - b^2 = (a - b)(a + b) with a=2xa = 2x and b=5b = 5.
2
Analyze the second expression x2−8x+15x^2 - 8x + 15.
It factors to (x−3)(x−5)(x - 3)(x - 5).
The constant term is positive and the middle coefficient is negative, so both factors must contain negative constants that multiply to 1515 and add to −8-8.
3
Analyze the third expression 3x2+12x−153x^2 + 12x - 15.
It factors to 3(x+5)(x−1)3(x + 5)(x - 1).
Factoring out the GCF of 33 gives 3(x2+4x−5)3(x^2 + 4x - 5). The resulting quadratic factors into binomials with constants 55 and −1-1.
4
Analyze the fourth expression 2x3−8x2x^3 - 8x.
It factors to 2x(x−2)(x+2)2x(x - 2)(x + 2).
Factoring out the GCF of 2x2x gives 2x(x2−4)2x(x^2 - 4). The expression x2−4x^2 - 4 is a difference of squares that further factors into (x−2)(x+2)(x - 2)(x + 2).

Anahtar Kavram

Factoring Polynomials
Tahmini Süre:2m 0s
Soru 2102Soru →

Which composite figure correctly corresponds to each set of geometric components? Match each set of transparent geometric components (Sets 1-3) to its correct superimposed composite figure (Figures X-Z). Assume the base square remains stationary while the overlay square undergoes the indicated rotation before being placed exactly on top of the base square.

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Öğeler

Set 1: Base square with a diagonal line from top-left to bottom-right. Overlay square has a solid circle in the top-left quadrant, rotated 90° clockwise.
Set 2: Base square with a diagonal line from bottom-left to top-right. Overlay square has a solid circle in the top-left quadrant, rotated 180°.
Set 3: Base square with a diagonal line from bottom-left to top-right. Overlay square has a solid circle in the bottom-left quadrant, rotated 90° clockwise.

Eşleşmeler

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Cevap

Set 1 matches Figure X, Set 2 matches Figure Z, and Set 3 matches Figure Y.
Each correct pairing strictly follows spatial transformation rules. By systematically tracking the starting quadrant of the circle in the overlay, applying the stated degree and direction of rotation, and laying it over the specified diagonal base, the correct composite image can be logically deduced.

Adım Adım Çözüm

1
Analyze Set 1 rotation and layering.
The top-left circle moves to the top-right. Placed over a top-left to bottom-right diagonal, this matches Figure X.
A 90-degree clockwise rotation shifts elements to the next adjacent quadrant in a clockwise direction.
2
Analyze Set 2 rotation and layering.
The top-left circle moves to the bottom-right. Placed over a bottom-left to top-right diagonal, this matches Figure Z.
A 180-degree rotation shifts elements diagonally to the completely opposite quadrant.
3
Analyze Set 3 rotation and layering.
The bottom-left circle moves to the top-left. Placed over a bottom-left to top-right diagonal, this matches Figure Y.
A 90-degree clockwise rotation shifts the bottom-left quadrant directly up to the top-left quadrant.

Anahtar Kavram

Superimposition of Shapes
Soru 2103Soru →

A drafter is reviewing a set of architectural plans. Connect each described geometric condition with its correct mathematical term.

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Öğeler

Two angles whose sum is exactly 180∘180^\circ
Two angles whose sum is exactly 90∘90^\circ
A pair of opposite, equal angles formed by two intersecting lines
Two straight lines that intersect to form a right angle

Eşleşmeler

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Cevap

Two angles summing to 180∘180^\circ match with Supplementary angles; two angles summing to 90∘90^\circ match with Complementary angles; opposite equal angles match with Vertical angles; lines forming a right angle match with Perpendicular lines.
Each definition precisely matches the fundamental geometric axioms for angles and lines. Recognizing these definitions is essential for solving more complex geometry problems.

Adım Adım Çözüm

1
Identify the geometric term for two angles whose sum is exactly 180∘180^\circ.
Supplementary angles
By geometric definition, a pair of angles that add up to 180∘180^\circ (forming a straight line if adjacent) are supplementary.
2
Identify the geometric term for two angles whose sum is exactly 90∘90^\circ.
Complementary angles
By geometric definition, a pair of angles that add up to 90∘90^\circ (forming a right angle if adjacent) are complementary.
3
Identify the term for the opposite angles created when two lines intersect.
Vertical angles
Intersecting lines create two pairs of non-adjacent, opposite angles known as vertical angles, which are congruent.
4
Identify the term for straight lines that intersect to form a right angle.
Perpendicular lines
When lines intersect at exactly 90∘90^\circ, they are defined mathematically as perpendicular.

Anahtar Kavram

Basic terminology for angle relationships and line intersections
Tahmini Süre:45s
Soru 2104Soru →

An isosceles triangle has a perimeter of 3636 centimeters. The base of the triangle measures 1010 centimeters. What is the area of the triangle in square centimeters?

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Cevap: 60

Cevap

60
To find the area, you must first know the perpendicular height. By splitting the isosceles triangle in half via its altitude, a right triangle is formed with a hypotenuse of 1313 (the side length) and a base of 55 (half of the full base). The Pythagorean theorem (52+h2=1325^2 + h^2 = 13^2) reveals the height is 1212. The full area is then calculated as 12×base×height\frac{1}{2} \times \text{base} \times \text{height}, which is 12×10×12=60\frac{1}{2} \times 10 \times 12 = 60.

Adım Adım Çözüm

1
Calculate the length of the two equal sides.
The two equal sides each measure 1313 centimeters.
The perimeter is 3636 cm and the base is 1010 cm. The remaining 2626 cm must be divided equally between the two identical legs: 26÷2=1326 \div 2 = 13 cm.
2
Determine the base of the right triangle formed by the altitude.
The base of the right triangle is 55 centimeters.
The altitude of an isosceles triangle bisects the base, splitting the 1010-centimeter base into two equal 55-centimeter segments.
3
Calculate the height using the Pythagorean theorem.
The height is 1212 centimeters.
In the right triangle formed, the hypotenuse is 1313 and one leg is 55. Let hh be the height. 52+h2=132⇒25+h2=169⇒h2=144⇒h=125^2 + h^2 = 13^2 \Rightarrow 25 + h^2 = 169 \Rightarrow h^2 = 144 \Rightarrow h = 12.
4
Calculate the total area of the triangle.
The area is 6060 square centimeters.
The area formula is 12×base×height\frac{1}{2} \times \text{base} \times \text{height}. Thus, 12×10×12=60\frac{1}{2} \times 10 \times 12 = 60.

Anahtar Kavram

Using the Pythagorean theorem to find missing dimensions in isosceles triangles to calculate area.
Soru 2105Soru →

An engineer battalion is transporting heavy equipment in a convoy to a forward operating base 210210 miles away. To arrive on schedule, the convoy must maintain an overall average speed of 4242 mph for the entire journey.

During the first leg, the convoy travels 120120 miles in 22 hours. They then halt for 3030 minutes to inspect the equipment.

What average speed must the convoy maintain for the remainder of the trip to achieve the target overall average speed?

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Cevap: 36 mph

Cevap

The convoy must maintain an average speed of 36 mph for the remainder of the trip.
To achieve an overall average speed of 4242 mph over 210210 miles, the total journey must take exactly 55 hours. The convoy has already used 2.52.5 hours (22 hours driving + 0.50.5 hours resting) and covered 120120 miles. This leaves 9090 miles to be covered in the remaining 2.52.5 hours. Dividing the remaining distance by the remaining time (90/2.590 / 2.5) gives the required speed of 3636 mph.

Adım Adım Çözüm

1
Calculate the total time required for the entire journey.
Total Time = 210 miles/42 mph=5 hours210 \text{ miles} / 42 \text{ mph} = 5 \text{ hours}.
To find the time available for the second leg, we first need to know the total time allowed for the mission.
2
Calculate the time spent on the first leg and the rest stop.
Time Spent = 2 hours+30 minutes=2.5 hours2 \text{ hours} + 30 \text{ minutes} = 2.5 \text{ hours}.
The rest stop must be included in the total elapsed time because the overall average speed accounts for the entire duration of the journey.
3
Determine the remaining distance and remaining time for the final leg.
Remaining Distance = 210−120=90 miles210 - 120 = 90 \text{ miles}.
Remaining Time = 5−2.5=2.5 hours5 - 2.5 = 2.5 \text{ hours}.
Subtracting the distance already covered and the time already spent gives the parameters for the final segment.
4
Calculate the required average speed for the final leg.
Speed = 90 miles/2.5 hours=36 mph90 \text{ miles} / 2.5 \text{ hours} = 36 \text{ mph}.
Average speed is always calculated as total distance divided by total time for that specific segment.

Anahtar Kavram

To find a missing speed in a multi-leg journey, use the total distance and target average speed to find the total allowed time. Subtract the time and distance already used (including rest stops) to find the parameters for the remaining leg.

Alternatif Yöntem

You can work entirely in minutes to avoid decimals. Total time is 300300 minutes. Time spent is 150150 minutes. Time remaining is 150150 minutes. Speed needed is 90 miles/150 minutes=0.6 miles per minute90 \text{ miles} / 150 \text{ minutes} = 0.6 \text{ miles per minute}. Multiply by 6060 to convert to 3636 mph.
Tahmini Süre:1m 30s
Soru 2106Soru →

If (x,y)(x, y) is the solution to the system of equations below, what is the value of the expression x+3yx + 3y?

3x−2y=143x - 2y = 14
x=y+5x = y + 5
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Cevap: 1

Cevap

The value of the expression is 1.
The system can be efficiently solved using substitution because the second equation already isolates xx. Substituting x=y+5x = y + 5 into the first equation yields 3(y+5)−2y=143(y + 5) - 2y = 14. Distributing the 33 gives 3y+15−2y=143y + 15 - 2y = 14, which simplifies to y=−1y = -1. Substituting this back into the second equation gives x=−1+5=4x = -1 + 5 = 4. Finally, the question asks for the value of x+3yx + 3y, which evaluates to 4+3(−1)=14 + 3(-1) = 1.

Adım Adım Çözüm

1
Substitute the expression for xx from the second equation into the first equation.
3(y+5)−2y=143(y + 5) - 2y = 14
This isolates a single variable, allowing us to solve for yy.
2
Distribute the 3 and solve the resulting equation for yy.
3y+15−2y=14⇒y+15=14⇒y=−13y + 15 - 2y = 14 \Rightarrow y + 15 = 14 \Rightarrow y = -1
Expanding the terms allows combining like terms to find the value of yy.
3
Substitute y=−1y = -1 back into the second equation to determine xx.
x=−1+5⇒x=4x = -1 + 5 \Rightarrow x = 4
Both values are needed for the final expression.
4
Evaluate the target expression x+3yx + 3y using the values found for xx and yy.
4+3(−1)=4−3=14 + 3(-1) = 4 - 3 = 1
The question specifically asks for the evaluated value of this expression, not just the ordered pair.

Anahtar Kavram

Solving a system of linear equations using the substitution method and evaluating an algebraic expression.
Soru 2107Soru →

An electronics store on a military base sells a laptop originally priced at 840840. The store offers a 25%25\% discount for service members. If a 6%6\% sales tax is applied to the discounted price, what is the final cost of the laptop?

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Cevap: 667.80667.80

Cevap

The final cost of the laptop is $667.80.
The correct answer is found by completing a two-step percentage calculation. First, the 25%25\% discount is applied to the $840\$840 original price (840×0.25=210840 \times 0.25 = 210), yielding a sale price of $630\$630. Then, the 6%6\% sales tax must be calculated on this new sale price (630×0.06=37.80630 \times 0.06 = 37.80) and added to it. Adding the tax to the sale price gives a final total of $667.80\$667.80.

Adım Adım Çözüm

1
Calculate the dollar amount of the military discount.
840×0.25=210840 \times 0.25 = 210
To find the discount, multiply the original price by the decimal equivalent of the percentage (25%=0.2525\% = 0.25).
2
Subtract the discount from the original price to find the sale price.
840−210=630840 - 210 = 630
The discount must be subtracted from the original price to determine the amount that will be taxed.
3
Calculate the amount of sales tax on the discounted price.
630×0.06=37.80630 \times 0.06 = 37.80
Sales tax is calculated as a percentage of the final sale price, not the original price.
4
Add the sales tax to the discounted price to find the total final cost.
630+37.80=667.80630 + 37.80 = 667.80
The final amount paid is the sum of the sale price and the calculated tax.

Anahtar Kavram

Calculating Percentages of Quantities

Alternatif Yöntem

Instead of calculating the discount amount and subtracting, you can determine what percentage of the price you will pay. If there is a 25%25\% discount, you pay 75%75\% of the original price (0.750.75). To include a 6%6\% tax, you multiply by 1.061.06. You can calculate the final price directly as: $840×0.75×1.06=$667.80\$840 \times 0.75 \times 1.06 = \$667.80.
Tahmini Süre:1m 30s
Soru 2108Soru →

A circular target has a diameter of 1010 inches. What is the area of the target in square inches?

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Cevap: 25π25\pi

Cevap

The correct answer is 25π25\pi square inches.
The correct area is found by first dividing the diameter of 1010 inches by 22 to get a radius of 55 inches. Squaring the radius gives 2525, which is then multiplied by π\pi to yield 25π25\pi square inches.

Adım Adım Çözüm

1
Find the radius of the circular target.
r=102=5r = \frac{10}{2} = 5 inches.
The area formula requires the radius, which is exactly half of the given diameter.
2
Apply the formula for the area of a circle.
A=πr2=π(5)2=25πA = \pi r^2 = \pi (5)^2 = 25\pi.
Substitute the calculated radius into the standard area formula to find the final square footage.

Anahtar Kavram

Area of a Circle
Soru 2109Soru →

Calculate the missing value based on the provided scenario.

Aşağıdaki boşlukları doldurun

A military hospital pharmacy currently stocks 850850 units of a specific antibiotic. If 38%38\% of this stock is distributed to various clinics on the base, there will be units remaining in the main pharmacy.
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Cevap

527
To find the number of remaining units, you can first subtract the distributed percentage from 100%100\% (100%−38%=62%100\% - 38\% = 62\%). Next, convert 62%62\% to a decimal (0.620.62) and multiply it by the total stock (0.62×850=5270.62 \times 850 = 527). Alternatively, you could calculate the number of units distributed (0.38×850=3230.38 \times 850 = 323) and subtract that amount from the original stock (850−323=527850 - 323 = 527).

Adım Adım Çözüm

1
Determine the percentage of the antibiotic stock that will remain.
$100\% - 38\% = 62\%
Since 38%38\% of the stock is distributed, the remainder is the difference between 100%100\% and 38%38\%.
2
Convert the remaining percentage to a decimal.
62%=0.6262\% = 0.62
Percentages must be converted into decimals or fractions before they can be used in multiplication.
3
Calculate 62%62\% of the total stock.
0.62×850=5270.62 \times 850 = 527
Multiplying the decimal representation of the remaining percentage by the total original stock gives the number of units left.

Anahtar Kavram

Calculating the remaining amount by applying the complementary percentage to a whole quantity.
Soru 2110Soru →

A guy wire is attached to the top of a 1212-foot vertical pole. The wire is anchored to the ground 55 feet from the base of the pole. What is the length of the guy wire?

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Cevap: 1313 feet

Cevap

The guy wire is 1313 feet long.
The length of the guy wire represents the hypotenuse of a right triangle formed by the pole and the ground. According to the Pythagorean theorem (a2+b2=c2a^2 + b^2 = c^2), the square of the hypotenuse equals the sum of the squares of the two legs. Substituting the given values: 122+52=144+25=16912^2 + 5^2 = 144 + 25 = 169. Taking the square root of 169169 gives 1313 feet.

Adım Adım Çözüm

1
Identify the known values representing the legs of the right triangle.
Leg a=5a = 5 feet, Leg b=12b = 12 feet.
The pole and the ground meet at a right angle, so they form the legs of the triangle.
2
Apply the Pythagorean theorem (a2+b2=c2a^2 + b^2 = c^2).
52+122=c25^2 + 12^2 = c^2
The theorem connects the lengths of the legs to the hypotenuse (the guy wire).
3
Square the lengths of the legs and sum them.
25+144=16925 + 144 = 169
This calculates the value of the hypotenuse squared (c2c^2).
4
Take the square root of the sum.
c=169=13c = \sqrt{169} = 13
This isolates cc and provides the actual length of the hypotenuse.

Anahtar Kavram

The Pythagorean theorem is used to find the hypotenuse of a right triangle when both legs are known.
Soru 2111Soru →

A cafe owner is purchasing a commercial espresso machine. Supplier A lists the machine for $2,000\$2,000 with a single 30%30\% discount. Supplier B lists the identical machine for $2,400\$2,400 with successive discounts of 25%25\% and 20%20\%. How much money will the owner save by purchasing the machine from the less expensive supplier?

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Cevap: $40\$40

Cevap

The owner will save $40 by choosing Supplier A.
Supplier A's final price is 1,400(whichis1,400 (which is 2,000 minus a 600discount).SupplierB′sfinalpriceis600 discount). Supplier B's final price is 1,440 (calculated by first reducing 2,400by252,400 by 25% to get 1,800, and then reducing 1,800by201,800 by 20% to get 1,440). The difference between the two prices is $40, making Supplier A the less expensive option by that amount.

Adım Adım Çözüm

1
Calculate the final price for Supplier A.
$2,000×0.30=$600\$2,000 \times 0.30 = \$600 discount. $2,000−$600=$1,400\$2,000 - \$600 = \$1,400.
A single discount is taken directly from the initial price.
2
Calculate the price after the first discount for Supplier B.
$2,400×0.25=$600\$2,400 \times 0.25 = \$600 discount. $2,400−$600=$1,800\$2,400 - \$600 = \$1,800.
The first of the successive discounts is applied to the original listing price.
3
Calculate the price after the second discount for Supplier B.
$1,800×0.20=$360\$1,800 \times 0.20 = \$360 discount. $1,800−$360=$1,440\$1,800 - \$360 = \$1,440.
The second discount must be applied to the new subtotal, not the original price.
4
Find the difference between the two final prices.
$1,440−$1,400=$40\$1,440 - \$1,400 = \$40.
Subtracting the lower price from the higher price gives the total savings.

Anahtar Kavram

Calculating successive discounts and comparing final sale prices.
Soru 2112Soru →

A vertical flagpole that is originally 3232 feet tall breaks at a certain height due to strong winds. The top part of the pole folds over without completely detaching, and the tip touches the level ground exactly 1616 feet away from the base of the pole. At what height from the ground did the flagpole break?

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Cevap: 12 feet

Cevap

12 feet
The scenario creates a right triangle where the vertical leg is the standing part of the pole, the horizontal leg is the ground, and the hypotenuse is the broken top part. Letting the break height be xx, the hypotenuse becomes (32−x)(32 - x). Using the Pythagorean theorem: x2+162=(32−x)2x^2 + 16^2 = (32 - x)^2. Expanding the right side gives x2+256=1024−64x+x2x^2 + 256 = 1024 - 64x + x^2. Subtracting x2x^2 from both sides simplifies the equation to 256=1024−64x256 = 1024 - 64x. Adding 64x64x and subtracting 256256 gives 64x=76864x = 768. Dividing by 6464 yields x=12x = 12. Therefore, the pole broke 1212 feet above the ground.

Adım Adım Çözüm

1
Define the variables for the sides of the right triangle formed by the broken flagpole.
Let the height of the break (standing part) be xx. The length of the fallen part (hypotenuse) is the remainder of the pole, which is (32−x)(32 - x). The base distance along the ground is 1616 feet.
Establishing these algebraic relationships is necessary to apply the Pythagorean theorem to the scenario.
2
Set up the Pythagorean theorem equation (a2+b2=c2a^2 + b^2 = c^2) using the defined variables.
x2+162=(32−x)2x^2 + 16^2 = (32 - x)^2
The standing pole and the ground form a right angle, making the standing pole and ground distance the legs, and the fallen part the hypotenuse.
3
Expand both sides of the algebraic equation.
x2+256=1024−64x+x2x^2 + 256 = 1024 - 64x + x^2
Expanding the squared binomial (32−x)2(32 - x)^2 correctly is required to isolate the variable xx.
4
Solve for xx by combining like terms.
Subtract x2x^2 from both sides to get 256=1024−64x256 = 1024 - 64x. Rearrange to 64x=76864x = 768, and divide by 6464 to find x=12x = 12.
Isolating xx provides the exact height from the ground where the flagpole snapped.

Anahtar Kavram

Applying the Pythagorean Theorem with algebraic expressions
Soru 2113Soru →

Match each fundamental geometric term related to a circle with its correct definition.

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Öğeler

Radius
Diameter
Circumference
Chord

Eşleşmeler

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Cevap

Radius matches with a line segment from the center to the edge; Diameter matches with a line segment passing through the center; Circumference matches with the total distance around the circle; Chord matches with a line segment connecting any two points on the circle.
Each geometric term possesses a precise mathematical definition that distinguishes its function and location within a circle. Correctly identifying these fundamental components is an essential prerequisite for performing geometric calculations such as finding area or circumference.

Adım Adım Çözüm

1
Identify the term that represents the perimeter or boundary distance of the circle.
Circumference matches with 'The total distance around the outer boundary of a circle.'
Circumference is the only term listed that measures a 1D distance around a shape rather than a straight interior line segment.
2
Differentiate between the line segments based on their relationship to the circle's center point.
Radius connects the center to the edge. Diameter passes all the way through the center from edge to edge.
This establishes the mathematical relationship where the diameter is exactly twice the length of the radius.
3
Determine the general term for a line segment connecting any two points on the circle's edge.
Chord matches with 'A line segment whose endpoints lie on the circle, but which does not necessarily pass through the center.'
A diameter is a special type of chord, but 'chord' is the broader category that does not require passing through the center.

Anahtar Kavram

Fundamental vocabulary and structural properties of circles.
Soru 2114Soru →

An armored cavalry troop conducts a training movement. They travel 4545 miles over rough terrain at a speed of 1515 miles per hour. After a 9090-minute halt for vehicle maintenance, they proceed 7575 miles along a highway at 5050 miles per hour. What is their overall average speed, in miles per hour, for the entire operation?

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Cevap: 20

Cevap

The overall average speed is 2020 miles per hour.
The correct answer is 2020 because average speed is the ratio of total distance to total time. The total distance is 120120 miles (45+7545 + 75). The total time includes the travel times (33 hours and 1.51.5 hours) plus the maintenance halt (1.51.5 hours), which equals 66 hours. Dividing 120120 miles by 66 hours gives an overall average speed of 2020 miles per hour.

Adım Adım Çözüm

1
Calculate the time taken for the first travel segment.
4515=3\frac{45}{15} = 3 hours
Time is required to determine the total elapsed time of the operation.
2
Convert the maintenance halt time from minutes to hours.
9090 minutes =1.5= 1.5 hours
All time units must be consistent (hours) before they can be added together.
3
Calculate the time taken for the second travel segment.
7550=1.5\frac{75}{50} = 1.5 hours
This gives the travel time for the final leg of the route.
4
Calculate the total distance traveled.
45+75=12045 + 75 = 120 miles
Total distance is the numerator in the average speed formula.
5
Calculate the total elapsed time for the entire operation.
3+1.5+1.5=63 + 1.5 + 1.5 = 6 hours
Total time is the denominator in the average speed formula, and it must include the maintenance halt.
6
Calculate the overall average speed.
1206=20\frac{120}{6} = 20 miles per hour
Average speed is defined as the total distance divided by the total time.

Anahtar Kavram

Average speed is calculated by dividing the total distance traveled by the total time elapsed, including any rest stops or delays.
Soru 2115Soru →

A quartermaster depot receives a shipment of 2,5002,500 emergency field rations. Upon inspection, 36%36\% of the rations are classified as vegetarian. Of these vegetarian rations, 15%15\% are also certified as gluten-free. How many gluten-free vegetarian rations are in the shipment?

Cevabı ve açıklamayı göster

Cevap: 135

Cevap

135
The correct answer is found by completing two sequential percentage calculations. First, find 36%36\% of the 2,5002,500 total rations (2,500×0.36=9002,500 \times 0.36 = 900). Then, find 15%15\% of those 900900 vegetarian rations (900×0.15=135900 \times 0.15 = 135).

Adım Adım Çözüm

1
Calculate the number of vegetarian rations by finding 36%36\% of the total 2,5002,500 rations.
2,500×0.36=9002,500 \times 0.36 = 900 vegetarian rations.
The first percentage applies to the entire shipment of rations.
2
Calculate the number of gluten-free vegetarian rations by finding 15%15\% of the result from step 1.
900×0.15=135900 \times 0.15 = 135 gluten-free vegetarian rations.
The problem asks for 15%15\% 'Of these vegetarian rations', meaning the base for the second percentage is 900900, not 2,5002,500.

Anahtar Kavram

Calculating percentages of a specified subset in a multi-step word problem.
Soru 2116Soru →

A landscaper is placing a decorative border around a circular flower bed. The radius of the flower bed is 1212 feet. What is the total length of the border needed in terms of π\pi?

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Cevap: 24π24\pi feet

Cevap

The total length of the border is 24π24\pi feet, which is found by calculating the circumference of the circle.
To find the total length of the border, you must calculate the circumference of the circular flower bed. The formula for circumference is C=2πrC = 2\pi r. Substituting the given radius of 1212 feet into the formula gives C=2⋅π⋅12=24πC = 2 \cdot \pi \cdot 12 = 24\pi feet.

Adım Adım Çözüm

1
Identify the mathematical concept required to find the length of a border around a circle.
The length of the border corresponds to the circumference of the circle.
Perimeter (circumference) measures the distance around the outside of a 2D shape.
2
Select the correct formula for the circumference of a circle.
Formula: C=2πrC = 2\pi r
The problem provides the radius (rr), so this is the most direct formula to use.
3
Substitute the given radius value into the formula and solve.
C=2⋅π⋅12=24πC = 2 \cdot \pi \cdot 12 = 24\pi feet.
Replacing rr with 1212 computes the exact circumference in terms of π\pi.

Anahtar Kavram

Circumference of a circle
Soru 2117Soru →

Given the system of linear equations below, what is the value of yy?

5x+2y=125x + 2y = 12
3x−4y=23x - 4y = 2
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Cevap: 1

Cevap

The correct value for y is 1.
By multiplying the first equation by 2, we get 10x + 4y = 24. Adding this to the second equation (3x - 4y = 2) eliminates y, resulting in 13x = 26, which simplifies to x = 2. Substituting x = 2 back into the first equation gives 5(2) + 2y = 12, or 10 + 2y = 12. Subtracting 10 from both sides leaves 2y = 2, yielding the final correct answer of y = 1.

Adım Adım Çözüm

1
Multiply the first equation by 2 to align the coefficients of y for elimination.
10x+4y=2410x + 4y = 24
Creating a +4y term in the first equation allows y to be eliminated when added to the -4y term in the second equation.
2
Add the modified first equation to the second equation.
(10x+3x)+(4y−4y)=24+2⇒13x=26(10x + 3x) + (4y - 4y) = 24 + 2 \Rightarrow 13x = 26
This eliminates the variable y, leaving a single-variable equation that can be easily solved for x.
3
Divide both sides by 13 to solve for x.
x=2x = 2
Isolating x provides the first part of the coordinate solution.
4
Substitute x = 2 back into the first original equation to solve for y.
5(2)+2y=12⇒10+2y=12⇒2y=2⇒y=15(2) + 2y = 12 \Rightarrow 10 + 2y = 12 \Rightarrow 2y = 2 \Rightarrow y = 1
Since the question asks specifically for the value of y, this final substitution step is required.

Anahtar Kavram

Solving Systems of Linear Equations using the Elimination Method
Soru 2118Soru →

A hiker walks 88 miles due north, then turns and walks 1515 miles due east. What is the straight-line distance, in miles, from the hiker's starting point to their current location?

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Cevap: 17

Cevap

17
Because the hiker's path consists of two perpendicular segments (north and east), they form the legs of a right triangle measuring 88 miles and 1515 miles. The straight-line distance from the start to the end is the hypotenuse of this triangle. Applying the Pythagorean theorem (a2+b2=c2a^2 + b^2 = c^2), we get 82+152=c28^2 + 15^2 = c^2, which simplifies to 64+225=28964 + 225 = 289. The square root of 289289 is 1717. Therefore, the straight-line distance is 1717 miles.

Adım Adım Çözüm

1
Visualize the geometrical shape formed by the hiker's path.
A right triangle is formed with legs of 88 miles and 1515 miles.
The directions 'due north' and 'due east' are perpendicular, creating a 90∘90^\circ angle.
2
Set up the Pythagorean theorem equation.
82+152=c28^2 + 15^2 = c^2
The straight-line distance corresponds to the hypotenuse (cc) of the right triangle.
3
Square the values of the legs and add them together.
64+225=28964 + 225 = 289
To evaluate the left side of the equation.
4
Calculate the square root of the sum.
c=289=17c = \sqrt{289} = 17
To solve for cc and find the final straight-line distance.

Anahtar Kavram

Calculating distance using the Pythagorean theorem
Soru 2119Soru →

Read the geometric scenario below and calculate the missing perimeter. Enter only the numerical value.

Aşağıdaki boşlukları doldurun

In △PQR\triangle PQR, an altitude PSPS is drawn to the base QRQR, creating two right triangles, △PQS\triangle PQS and △PSR\triangle PSR. If the length of side PQPQ is 1313 units, the length of side PRPR is 1515 units, and the altitude PSPS is 1212 units, the perimeter of the entire △PQR\triangle PQR is units.
Cevabı ve açıklamayı göster

Cevap

42
To find the perimeter of △PQR\triangle PQR, we need the lengths of its three outer sides: PQPQ, PRPR, and QRQR. We are given PQ=13PQ = 13 and PR=15PR = 15. The altitude PSPS divides QRQR into two segments, QSQS and SRSR, forming two right triangles. Using the Pythagorean theorem in △PQS\triangle PQS, we find QS=132−122=25=5QS = \sqrt{13^2 - 12^2} = \sqrt{25} = 5. Using the Pythagorean theorem in △PSR\triangle PSR, we find SR=152−122=81=9SR = \sqrt{15^2 - 12^2} = \sqrt{81} = 9. The total base is QR=QS+SR=5+9=14QR = QS + SR = 5 + 9 = 14. The perimeter is the sum of the outer sides: 13+15+14=4213 + 15 + 14 = 42.

Adım Adım Çözüm

1
Use the Pythagorean theorem in right △PQS\triangle PQS to find the length of base segment QSQS.
QS=132−122=169−144=25=5QS = \sqrt{13^2 - 12^2} = \sqrt{169 - 144} = \sqrt{25} = 5
The altitude PSPS forms a right angle with the base, making PQPQ the hypotenuse. The missing leg is found by subtracting the square of the altitude from the square of the hypotenuse.
2
Use the Pythagorean theorem in right △PSR\triangle PSR to find the length of base segment SRSR.
SR=152−122=225−144=81=9SR = \sqrt{15^2 - 12^2} = \sqrt{225 - 144} = \sqrt{81} = 9
Similarly, PRPR is the hypotenuse of the second right triangle, so the missing leg is found by subtracting the square of the altitude from the square of this hypotenuse.
3
Calculate the total length of the base QRQR.
QR=QS+SR=5+9=14QR = QS + SR = 5 + 9 = 14
The entire base QRQR is the sum of the two segments created by the altitude.
4
Calculate the perimeter of the full △PQR\triangle PQR.
Perimeter = PQ+PR+QR=13+15+14=42PQ + PR + QR = 13 + 15 + 14 = 42
The perimeter is the total length of the outer boundary of the triangle, which is the sum of its three main sides.

Anahtar Kavram

Applying the Pythagorean theorem in multi-step geometric figures to find missing side lengths and perimeter.
Tahmini Süre:2m 0s
Soru 2120Soru →

An auto repair shop owner orders a bulk supply of replacement brake pads with an original total cost of $800\$800. The automotive parts distributor applies a 15%15\% bulk discount to the order. In addition, the shop receives an extra 5%5\% discount on the reduced price for paying the invoice in full upon delivery.

Determine the shop's final purchase price for the brake pads and the total amount of money saved compared to the original cost.

Aşağıdaki boşlukları doldurun

The final purchase price is $\$andthetotalamountsavedis and the total amount saved is \$$.
Cevabı ve açıklamayı göster

Cevap

The final purchase price is 646andthetotalamountsavedis646 and the total amount saved is 154.
The correct final price is found by taking 15% off 800toget800 to get 680, then taking 5% off 680toarriveat680 to arrive at 646. The total savings is the sum of both discounts (120+120 + 34 = $154).

Adım Adım Çözüm

1
Calculate the amount of the 15% bulk discount.
$800×0.15=$120\$800 \times 0.15 = \$120
To find the savings provided by the initial distributor discount.
2
Calculate the intermediate price after the first discount.
$800−$120=$680\$800 - \$120 = \$680
The subsequent 5% discount must be applied to this reduced price, not the original price.
3
Calculate the amount of the 5% payment discount.
$680×0.05=$34\$680 \times 0.05 = \$34
To determine the additional savings from paying the invoice in full upon delivery.
4
Calculate the final purchase price.
$680−$34=$646\$680 - \$34 = \$646
This is the final amount the shop must pay after all successive discounts have been applied.
5
Calculate the total amount saved.
$120+$34=$154\$120 + \$34 = \$154
To find the complete difference between the original cost and the final price.

Anahtar Kavram

Successive discounts must be calculated sequentially on the new reduced price at each step, rather than adding the percentages together.
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