Tüm alıştırma soruları

5556 soru

Soru 5281Soru

A straight ramp connects a driveway to a loading dock that is 1010 feet above the ground. The ramp forms an angle θ\theta with the flat ground such that tan(θ)=512\tan(\theta) = \frac{5}{12}. What is the length, in feet, of the ramp?

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Cevap: 2626

Cevap

The length of the ramp is 2626 feet.
In the right triangle formed by the ground, the loading dock, and the ramp, the dock height (1010 feet) is opposite angle θ\theta, and the ramp is the hypotenuse. Since tan(θ)=oppositeadjacent=512\tan(\theta) = \frac{\text{opposite}}{\text{adjacent}} = \frac{5}{12}, setting 10adjacent=512\frac{10}{\text{adjacent}} = \frac{5}{12} yields an adjacent side of 2424 feet. Applying the Pythagorean theorem to find the hypotenuse gives 102+242=676=26\sqrt{10^2 + 24^2} = \sqrt{676} = 26 feet.

Adım Adım Çözüm

1
Identify the given information and trigonometric ratio.
The vertical leg opposite angle θ\theta is 1010 feet. The ratio is tan(θ)=oppositeadjacent=512\tan(\theta) = \frac{\text{opposite}}{\text{adjacent}} = \frac{5}{12}.
Tangent is defined as the ratio of the side opposite the angle to the side adjacent to the angle in a right triangle.
2
Solve for the length of the adjacent leg (ground distance).
10adjacent=512    adjacent=10×125=24\frac{10}{\text{adjacent}} = \frac{5}{12} \implies \text{adjacent} = \frac{10 \times 12}{5} = 24 feet.
Cross-multiplying gives the length of the ground leg.
3
Calculate the length of the ramp (hypotenuse) using the Pythagorean theorem.
\text{ramp length} = \sqrt{10^2 + 24^2} = \sqrt{100 + 576} = \sqrt{676} = 26\text{ feet}.
The ramp forms the hypotenuse of the right triangle, so its length is c=a2+b2c = \sqrt{a^2 + b^2}.

Anahtar Kavram

Right Triangle Trigonometry (SOHCAHTOA) and Pythagorean Theorem
Tahmini Süre:1m 15s
Soru 5282Soru

A solar power system generated a total of 450450 kilowatt-hours (kWh) of electricity during a 3-day period. On Day 1, the system generated 29\frac{2}{9} of the total 3-day electricity. On Day 2, it generated 40%40\% of the remaining electricity after Day 1. How many kilowatt-hours of electricity were generated on Day 3?

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Cevap: 210

Cevap

210 kWh
To find the electricity generated on Day 3, first determine the Day 1 portion by multiplying 29\frac{2}{9} by 450450, which gives 100100 kWh. The amount remaining for Days 2 and 3 is 450100=350450 - 100 = 350 kWh. Day 2 accounts for 40%40\% of this remaining amount, which is 0.40×350=1400.40 \times 350 = 140 kWh. Finally, subtract Day 2's portion from the remaining amount: 350140=210350 - 140 = 210 kWh.

Adım Adım Çözüm

1
Calculate the amount of electricity generated on Day 1.
100100 kWh
Multiply the fraction 29\frac{2}{9} by the total electricity (450450 kWh).
2
Determine the remaining electricity after Day 1.
350350 kWh
Subtract Day 1's generation (100100 kWh) from the total amount (450450 kWh).
3
Calculate the amount of electricity generated on Day 2.
140140 kWh
Convert 40%40\% to a decimal (0.400.40) and multiply by the remaining 350350 kWh.
4
Calculate the amount of electricity generated on Day 3.
210210 kWh
Subtract Day 2's generation (140140 kWh) from the 350350 kWh remaining after Day 1.

Anahtar Kavram

Multi-step word problems involving fractions, percentage calculations, and remaining quantities.
Tahmini Süre:1m 15s
Soru 5283Soru

A community library's summer program requires participants to create a 3-book reading list consisting of exactly 11 biography, 11 science fiction novel, and 11 history book selected from a featured list. The featured list contains 55 biographies (2 of which have over 400400 pages), 66 science fiction novels (3 of which have over 400400 pages), and 44 history books (1 of which has over 400400 pages). If a participant selects 11 book of each genre at random from the featured list, what is the probability that at least 11 of the selected books has over 400400 pages? Express your answer as a decimal.

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Cevap: 0.775

Cevap

0.775
To find the probability of selecting at least one book over 400400 pages, it is most efficient to use the complement rule: P(at least one)=1P(none)P(\text{at least one}) = 1 - P(\text{none}). There are 5×6×4=1205 \times 6 \times 4 = 120 total 3-book combinations. The number of books with 400400 pages or fewer in each category are 33 biographies, 33 sci-fi novels, and 33 history books. Thus, there are 3×3×3=273 \times 3 \times 3 = 27 combinations with no books over 400400 pages. The probability of choosing no books over 400400 pages is 27120=0.225\frac{27}{120} = 0.225. Subtracting this from 11 gives 10.225=0.7751 - 0.225 = 0.775.

Adım Adım Çözüm

1
Calculate the total number of possible combinations of selecting 1 book from each genre
Total combinations = 5×6×4=1205 \times 6 \times 4 = 120
By the Fundamental Counting Principle, multiplying the number of choices in each independent category yields the total outcomes.
2
Determine the complement event: selecting a reading list where NO book has over 400 pages
Available books of 400 pages or fewer: 3 biographies, 3 sci-fi novels, and 3 history books
Subtracting the number of books over 400 pages from the total in each category gives the count of books with 400 pages or fewer.
3
Calculate the number of combinations consisting entirely of books with 400 pages or fewer
Complement combinations = 3×3×3=273 \times 3 \times 3 = 27
Applying the Fundamental Counting Principle to the non-qualifying choices gives the total outcomes for the complement event.
4
Find the probability of the complement event and subtract from 1 to find the target probability
P(at least one over 400)=127120=10.225=0.775P(\text{at least one over } 400) = 1 - \frac{27}{120} = 1 - 0.225 = 0.775
The complement rule states that P(A)=1P(A)P(A) = 1 - P(A'), which is much more efficient than calculating probabilities for 1, 2, or 3 long books separately.

Anahtar Kavram

Complementary Probability and Fundamental Counting Principle
Tahmini Süre:1m 30s
Soru 5284Soru

A high school science club organized a daily recycling drive over a 10-day period. The frequency table below summarizes the number of aluminum cans collected per day:

Cans Collected Per DayNumber of Days
102
203
303
401
501

What is the positive difference between the mean number of cans collected per day and the median number of cans collected per day?

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Cevap: 1

Cevap

The positive difference between the mean and median is 1.
To find the mean, calculate the weighted sum of the products of each daily quantity and its frequency: (10 × 2 + 20 × 3 + 30 × 3 + 40 × 1 + 50 × 1) = 260. Dividing 260 by the total 10 days gives a mean of 26. To find the median, list the 10 data points in order: 10, 10, 20, 20, 20, 30, 30, 30, 40, 50. The middle two numbers are the 5th and 6th terms (20 and 30), so the median is (20 + 30) / 2 = 25. Subtracting 25 from 26 yields a positive difference of 1.

Adım Adım Çözüm

1
Calculate the total number of cans collected and the total number of days.
Total days = 2 + 3 + 3 + 1 + 1 = 10. Total cans = (10 × 2) + (20 × 3) + (30 × 3) + (40 × 1) + (50 × 1) = 20 + 60 + 90 + 40 + 50 = 260.
To find the mean from a frequency table, multiply each data value by its frequency and sum the results, then divide by the total frequency.
2
Calculate the mean number of cans collected per day.
Mean = 260 / 10 = 26.
Divide the total sum of collected cans by the total number of days.
3
Find the median of the data set.
The 10 ordered data points are: 10, 10, 20, 20, 20, 30, 30, 30, 40, 50. The 5th value is 20 and the 6th value is 30. Median = (20 + 30) / 2 = 25.
For an even number of data points (N=10N = 10), the median is the arithmetic mean of the two middle values (N/2N/2 th and (N/2+1)(N/2 + 1) th terms).
4
Compute the positive difference between the mean and median.
Difference = 26 - 25 = 1.
Subtract the median from the mean to find the requested difference.

Anahtar Kavram

Weighted Mean and Median from Frequency Tables
Tahmini Süre:1m 15s
Soru 5285Soru

A circle in the standard (x,y)(x, y) coordinate plane is represented by the equation x2+y2+4x6y12=0x^2 + y^2 + 4x - 6y - 12 = 0. What is the distance between the two points where this circle intersects the xx-axis?

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Cevap: 8

Cevap

The distance between the two points where the circle intersects the xx-axis is 8 units.
Setting y=0y = 0 gives the quadratic equation x2+4x12=0x^2 + 4x - 12 = 0. Factoring yields (x+6)(x2)=0(x + 6)(x - 2) = 0, giving solutions x=6x = -6 and x=2x = 2. The distance between these two xx-intercepts is 2(6)=82 - (-6) = 8 units.

Adım Adım Çözüm

1
Substitute y=0y = 0 into the circle equation.
x2+4x12=0x^2 + 4x - 12 = 0
Points on the xx-axis have a yy-coordinate of 0.
2
Solve the quadratic equation for xx by factoring.
x=6x = -6 and x=2x = 2
Factoring (x+6)(x2)=0(x + 6)(x - 2) = 0 yields the xx-coordinates of the intersection points.
3
Find the distance between (6,0)(-6, 0) and (2,0)(2, 0).
2(6)=82 - (-6) = 8
The horizontal distance between two points (x1,0)(x_1, 0) and (x2,0)(x_2, 0) is x2x1|x_2 - x_1|.

Anahtar Kavram

Finding xx-intercepts of a circle given in general form
Soru 5286Soru

A team of plant physiologists investigated the transpiration rate of four plant species (Species W, X, Y, and Z) under two distinct light conditions—Low Intensity (150 μmol/m2/s150\text{ }\mu\text{mol/m}^2\text{/s}) and High Intensity (800 μmol/m2/s800\text{ }\mu\text{mol/m}^2\text{/s})—at a controlled temperature of 25C25^\circ\text{C}. The measured rates are shown in the table below:

Plant SpeciesTranspiration Rate at Low Intensity (mg H2O/cm2/hr\text{mg H}_2\text{O/cm}^2\text{/hr})Transpiration Rate at High Intensity (mg H2O/cm2/hr\text{mg H}_2\text{O/cm}^2\text{/hr})
Species W1.21.24.84.8
Species X2.52.56.56.5
Species Y0.80.83.23.2
Species Z1.51.55.55.5

Based on the table, what was the average increase in transpiration rate (in mg H2O/cm2/hr\text{mg H}_2\text{O/cm}^2\text{/hr}) across all four plant species when light condition was increased from Low Intensity to High Intensity?

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Cevap: 3.5 mg H2O/cm2/hr3.5\text{ mg H}_2\text{O/cm}^2\text{/hr}

Cevap

The average increase in transpiration rate across the four species is 3.5 mg H2O/cm2/hr3.5\text{ mg H}_2\text{O/cm}^2\text{/hr}.
To find the average increase, first subtract the Low Intensity transpiration rate from the High Intensity transpiration rate for each of the four species: Species W (4.81.2=3.64.8 - 1.2 = 3.6), Species X (6.52.5=4.06.5 - 2.5 = 4.0), Species Y (3.20.8=2.43.2 - 0.8 = 2.4), and Species Z (5.51.5=4.05.5 - 1.5 = 4.0). Adding these four increases yields a total of 14.0 mg H2O/cm2/hr14.0\text{ mg H}_2\text{O/cm}^2\text{/hr}. Dividing this sum by 44 species gives an average increase of 3.5 mg H2O/cm2/hr3.5\text{ mg H}_2\text{O/cm}^2\text{/hr}.

Adım Adım Çözüm

1
Calculate the difference between High Intensity and Low Intensity transpiration rates for each species.
Species W: 4.81.2=3.6 mg H2O/cm2/hr4.8 - 1.2 = 3.6\text{ mg H}_2\text{O/cm}^2\text{/hr}; Species X: 6.52.5=4.0 mg H2O/cm2/hr6.5 - 2.5 = 4.0\text{ mg H}_2\text{O/cm}^2\text{/hr}; Species Y: 3.20.8=2.4 mg H2O/cm2/hr3.2 - 0.8 = 2.4\text{ mg H}_2\text{O/cm}^2\text{/hr}; Species Z: 5.51.5=4.0 mg H2O/cm2/hr5.5 - 1.5 = 4.0\text{ mg H}_2\text{O/cm}^2\text{/hr}.
Determines the specific rate increase for each trial.
2
Sum the calculated rate increases across all four species.
3.6+4.0+2.4+4.0=14.0 mg H2O/cm2/hr3.6 + 4.0 + 2.4 + 4.0 = 14.0\text{ mg H}_2\text{O/cm}^2\text{/hr}.
Aggregates the individual increases to calculate the total change.
3
Divide the total sum of increases by the number of species (44) to determine the mean increase.
14.0/4=3.5 mg H2O/cm2/hr14.0 / 4 = 3.5\text{ mg H}_2\text{O/cm}^2\text{/hr}.
Yields the average (mean) change in transpiration rate per species.

Anahtar Kavram

Calculating mean changes and rate differences from tabular data
Tahmini Süre:1m 0s
Soru 5287Soru

Experiment 1
Students conducted a gravimetric analysis to determine the phosphate concentration in a water sample by precipitating magnesium ammonium phosphate hexahydrate (MgNH4PO46H2O\text{MgNH}_4\text{PO}_4 \cdot 6\text{H}_2\text{O}). The apparatus included a Büchner funnel, a heavy-walled filter flask attached to a vacuum aspirator line, filter paper, a wash bottle filled with ice-cold dilute ammonia solution, and an oven.

To ensure quantitative transfer, efficient impurity removal, and accurate final mass measurement of the precipitate without losing product, in what chronological order should the students perform the following steps of the filtration and drying procedure?

Öğeleri doğru sıraya koymak için sürükleyin

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Cevap

The correct sequence is to first seat and moisten the filter paper under vacuum, second pour the reaction mixture slurry to collect the precipitate, third rinse the filter cake with ice-cold wash solution, and fourth air-dry under vacuum before heating in a drying oven to constant mass.
The correct order follows standard laboratory protocol for gravimetric vacuum filtration: seating the filter paper prevents solids from leaking past the filter edges; pouring collects the bulk solid; washing cleans residual dissolved ions from the solid filter cake; and final oven drying removes moisture to allow accurate mass measurement.

Adım Adım Çözüm

1
Identify the initial setup requirement for vacuum filtration.
Moistening and vacuum-seating the filter paper must occur first.
If the paper is not seated tightly with liquid prior to adding the slurry, solid precipitate can leak underneath the paper edges and be lost in the filtrate.
2
Determine the primary separation step.
Pouring the reaction mixture slurry onto the prepared funnel.
Filtration separates the solid precipitate cake from the liquid supernatant.
3
Identify the purification step.
Washing the collected solid with ice-cold dilute ammonia.
Washing removes soluble surface impurities clinging to the solid cake; doing this after pouring ensures maximum liquid-solid contact.
4
Determine the final isolation and drying step.
Air-drying under vacuum followed by drying in an oven to constant mass.
Drying must occur last because any prior step involving washing or liquid transfer would reintroduce moisture, invalidating mass measurements.

Anahtar Kavram

Chronological execution and function of vacuum filtration apparatus steps
Soru 5288Soru

A technician is installing a straight support beam for a solar panel array mounted on a flat roof. The beam forms a right triangle with the horizontal roof and a vertical panel frame. The vertical frame is 2424 inches tall, and the angle θ\theta between the support beam and the horizontal roof satisfies sin(θ)=1213\sin(\theta) = \frac{12}{13}. What is the horizontal distance, in inches, along the roof from the bottom of the vertical frame to the anchor point of the support beam?

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Cevap: 10

Cevap

The horizontal distance along the roof from the bottom of the frame to the anchor point is 10 inches.
In a right-angled triangle formed by the vertical frame, horizontal roof, and diagonal support beam, the angle θ\theta is between the beam and the roof. The vertical frame (24 inches) is the side opposite to θ\theta. Using the sine definition, sin(θ)=oppositehypotenuse=1213\sin(\theta) = \frac{\text{opposite}}{\text{hypotenuse}} = \frac{12}{13}, so 24hypotenuse=1213\frac{24}{\text{hypotenuse}} = \frac{12}{13}, which yields a hypotenuse length of 26 inches. Applying the Pythagorean theorem to find the horizontal adjacent leg gives 262242=100=10\sqrt{26^2 - 24^2} = \sqrt{100} = 10 inches.

Adım Adım Çözüm

1
Identify the sides of the right triangle relative to the angle θ\theta.
The vertical frame of length 24 inches is opposite to θ\theta, the support beam is the hypotenuse, and the horizontal distance along the roof is adjacent to θ\theta.
SOHCAHTOA defines sin(θ)=oppositehypotenuse\sin(\theta) = \frac{\text{opposite}}{\text{hypotenuse}}.
2
Calculate the length of the hypotenuse using the sine ratio.
24hypotenuse=1213    hypotenuse=24×1312=26\frac{24}{\text{hypotenuse}} = \frac{12}{13} \implies \text{hypotenuse} = 24 \times \frac{13}{12} = 26 inches.
Setting the opposite side (24) over hypotenuse equal to 1213\frac{12}{13} allows solving for the hypotenuse.
3
Calculate the horizontal adjacent side using the Pythagorean theorem.
adjacent=262242=676576=100=10\text{adjacent} = \sqrt{26^2 - 24^2} = \sqrt{676 - 576} = \sqrt{100} = 10 inches.
In a right triangle, a2+b2=c2a^2 + b^2 = c^2, so the unknown leg is c2b2\sqrt{c^2 - b^2}.

Anahtar Kavram

Right Triangle Trigonometry (SOHCAHTOA)
Tahmini Süre:1m 15s
Soru 5289Soru

A soil scientist investigated the effect of varying soil copper (Cu2+\text{Cu}^{2+}) concentrations on the rate of nitrate uptake in spinach roots. Five groups of ten plants each were grown in identical hydroponic solutions containing Cu2+\text{Cu}^{2+} concentrations of 0 μM0\text{ }\mu\text{M}, 5 μM5\text{ }\mu\text{M}, 10 μM10\text{ }\mu\text{M}, 25 μM25\text{ }\mu\text{M}, and 50 μM50\text{ }\mu\text{M}, respectively. Throughout the 14-day experiment, all plant groups were maintained at 22C22^\circ\text{C} under a constant 16-hour light / 8-hour dark cycle. At the conclusion of the experiment, the researcher recorded the total nitrate concentration (μmol/g\mu\text{mol/g}) remaining in the nutrient solutions.

In this investigation, which factor serves as the independent variable?

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Cevap: The copper (Cu2+\text{Cu}^{2+}) concentration in the hydroponic solution

Cevap

The copper (Cu2+\text{Cu}^{2+}) concentration in the hydroponic solution
The independent variable is the specific factor that the experimenter purposely alters or varies between groups to observe its effect. In this study, the scientist systematically changed the copper concentration across five experimental groups (0 μM0\text{ }\mu\text{M} to 50 μM50\text{ }\mu\text{M}), making copper concentration the independent variable.

Adım Adım Çözüm

1
Identify the factor being systematically changed or manipulated by the researcher.
The researcher intentionally established five different hydroponic solution treatments with distinct copper (Cu2+\text{Cu}^{2+}) concentrations (00, 55, 1010, 2525, and 50 μM50\text{ }\mu\text{M}).
The manipulated condition across experimental setups defines the independent variable.
2
Distinguish the independent variable from dependent and controlled variables.
The nitrate remaining in solution is the measured outcome (dependent variable), while temperature and light cycle are kept constant across groups (controlled variables).
Ensures that the variable directly tested is isolated from confounding factors and measured outputs.

Anahtar Kavram

Identifying Independent, Dependent, and Controlled Variables
Soru 5290Soru

Astrophysicists measured the transit depth (percentage of starlight blocked) for four exoplanets orbiting a host star at two observation wavelengths (0.5 μm0.5\ \mu\text{m} and 1.5 μm1.5\ \mu\text{m}), as recorded in the table below:

ExoplanetTransit Depth at 0.5 μm0.5\ \mu\text{m} (%)Transit Depth at 1.5 μm1.5\ \mu\text{m} (%)
Exoplanet 11.21.8
Exoplanet 22.52.1
Exoplanet 30.81.6
Exoplanet 43.03.6

True or False: The mean transit depth across all four exoplanets measured at 1.5 μm1.5\ \mu\text{m} is 0.4%0.4\% greater than the mean transit depth measured at 0.5 μm0.5\ \mu\text{m}.

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Cevap: True

Cevap

The statement is True.
The mean transit depth at 1.5 μm is 2.275%, and the mean transit depth at 0.5 μm is 1.875%. Subtracting 1.875% from 2.275% gives exactly 0.4%, making the true/false statement correct.

Adım Adım Çözüm

1
Calculate the mean transit depth at 0.5 μm.
Sum = 1.2 + 2.5 + 0.8 + 3.0 = 7.5%. Mean = 7.5 / 4 = 1.875%.
Determines the baseline average value for the first wavelength column.
2
Calculate the mean transit depth at 1.5 μm.
Sum = 1.8 + 2.1 + 1.6 + 3.6 = 9.1%. Mean = 9.1 / 4 = 2.275%.
Determines the target average value for the second wavelength column.
3
Calculate the difference between the two averages.
2.275% - 1.875% = 0.4%.
Compares the calculated difference against the claimed value of 0.4%.

Anahtar Kavram

Calculating and comparing average values from structured tabular data
Soru 5291Soru

While studying historical climate patterns, dendrochronologists collected core samples from ancient bristlecone pines, they measured the ring widths with microscopes, and cross-dated the growth patterns against established regional master chronologies.

Which choice provides the correct punctuation and grammatical structure for the underlined portion?

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Cevap: pines, measured the ring widths with microscopes, and cross-dated

Cevap

pines, measured the ring widths with microscopes, and cross-dated
The correct phrasing creates a parallel list of three verb phrases ('collected core samples...', 'measured the ring widths...', and 'cross-dated the growth patterns...') that all share the subject 'dendrochronologists'. Commas are correctly used to separate each item in the three-part series, including the serial comma before the coordinating conjunction 'and'.

Adım Adım Çözüm

1
Identify the grammatical structure of the sentence
The sentence consists of a single subject ('dendrochronologists') performing three sequential actions in a list format.
Recognizing that the actions form a series of parallel verb phrases dictates the appropriate punctuation rules.
2
Analyze parallel verb series punctuation
Three items in a series require commas separating each item: item 1 ('collected...'), item 2 ('measured...'), and item 3 ('cross-dated...').
Items in a list must maintain parallel construction without introducing unnecessary pronouns or semicolons.
3
Select the option with clean list separation and correct comma placement
The phrase 'pines, measured the ring widths with microscopes, and cross-dated' correctly maintains parallelism and proper list commas.
This choice avoids creating a comma splice or splitting the verb from its direct object.

Anahtar Kavram

Commas with parallel items in a series
Tahmini Süre:45s
Soru 5292Soru

A community theater group allocated a total budget of $1,500\$1,500 to create costumes for an upcoming production. Exactly 14\frac{1}{4} of the budget was spent on fabric, 0.300.30 of the budget was spent on specialized footwear, and 15\frac{1}{5} of the budget was spent on sewing accessories. The remaining amount of the budget was spent on theatrical wigs. What amount, in dollars, did the theater group spend on theatrical wigs?

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Cevap: $375\$375

Cevap

The theater group spent $375\$375 on theatrical wigs.
The correct answer of $375\$375 is found by determining each individual expense and subtracting their sum from the total budget. Fabric accounts for 14\frac{1}{4} of $1,500\$1,500, which is $375\$375. Footwear accounts for 0.300.30 of $1,500\$1,500, which is $450\$450. Sewing accessories account for 15\frac{1}{5} of $1,500\$1,500, which is $300\$300. Combined, these three categories equal $375+$450+$300=$1,125\$375 + \$450 + \$300 = \$1,125. Subtracting $1,125\$1,125 from the total budget of $1,500\$1,500 leaves $375\$375 for theatrical wigs.

Adım Adım Çözüm

1
Calculate the dollar amount spent on fabric
14×$1,500=$375\frac{1}{4} \times \$1,500 = \$375
Multiply the fraction representing fabric by the total budget.
2
Calculate the dollar amount spent on footwear
0.30×$1,500=$4500.30 \times \$1,500 = \$450
Multiply the decimal representing footwear by the total budget.
3
Calculate the dollar amount spent on sewing accessories
15×$1,500=$300\frac{1}{5} \times \$1,500 = \$300
Multiply the fraction representing accessories by the total budget.
4
Sum the three known category expenses
\$375 + \$450 + \$300 = \$1,125
Add the expenses together to determine the total spent before wigs.
5
Subtract the sum of known expenses from the total budget
\$1,500 - \$1,125 = \$375
The remaining portion of the budget is allocated to theatrical wigs.

Anahtar Kavram

Converting fractions and decimals to quantities of a total amount and calculating remaining portions.
Soru 5293Soru

Read the passage below:

When volcanologist Dr. Helen Vance published her definitive report on Mount Searing's tephra stratigraphy in 2012, few realized how many years of groundwork had preceded the milestone. Her interest in the island crater was originally sparked back in 2004, when she unexpectedly detected anomalous glass shards while analyzing archived sediment cores in her university laboratory. To prepare for direct field sampling, Dr. Vance secured a specialized micro-X-ray fluorescence spectrometer in 2005. This crucial acquisition allowed her to launch her initial expedition to Mount Searing in 2006. It was not until her 2009 follow-up survey, however, that she collected the basaltic samples that ultimately validated her eruption timeline.

According to the passage, which of the following events occurred FIRST chronologically?

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Cevap: Dr. Vance analyzed archived sediment cores in her university laboratory.

Cevap

Dr. Vance analyzed archived sediment cores in her university laboratory.
The passage explicitly states that Dr. Vance's interest was sparked in 2004 when she analyzed archived sediment cores. This is the earliest event in the described timeline, preceding her equipment acquisition in 2005, her initial trip in 2006, her follow-up survey in 2009, and her publication in 2012.

Adım Adım Çözüm

1
Identify all temporal references and associated events mentioned in the passage.
2012: Published definitive report; 2004: Analyzed archived sediment cores and found glass shards; 2005: Secured spectrometer; 2006: Launched initial expedition; 2009: Collected basaltic samples during follow-up survey.
Tracking explicitly stated dates and sequence markers establishes the complete chronological order of events.
2
Determine which event happened earliest in time based on the text.
The earliest date explicitly mentioned is 2004, when Dr. Vance analyzed sediment cores in her laboratory.
Comparing the timeline markers reveals that 2004 predates all other listed events (2005, 2006, 2009, and 2012).

Anahtar Kavram

Determining Stated Sequence of Events
Tahmini Süre:1m 0s
Soru 5294Soru

During nocturnal field observations in tropical rainforests, entomologists recorded firefly species that produced rhythmic bright flashes, and they transmitted these signals across the dense canopy. Which choice best completes the sentence according to the conventions of standard written English?

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Cevap: , bright flashes, and they transmitted

Cevap

The choice containing ', bright flashes, and they transmitted' correctly punctuates the sentence.
The correct response inserts a comma between the coordinate adjectives 'rhythmic' and 'bright' because both adjectives independently modify 'flashes'. Furthermore, it retains the comma prior to the coordinating conjunction 'and' to properly separate two complete independent clauses.

Adım Adım Çözüm

1
Determine if 'rhythmic' and 'bright' are coordinate adjectives.
Because both 'rhythmic' and 'bright' modify 'flashes' independently (e.g., one can say 'rhythmic and bright flashes'), a comma is required between them.
Coordinate adjectives that modify the same noun must be separated by a comma.
2
Analyze the clause structure following the noun phrase.
The clause 'they transmitted these signals across the dense canopy' is independent because it contains its own subject ('they') and verb ('transmitted').
When two independent clauses are joined by a coordinating conjunction like 'and', a comma must precede the conjunction.
3
Select the option meeting both punctuation requirements.
The correct selection provides a comma after 'rhythmic' (yielding 'rhythmic, bright flashes') and keeps the comma before 'and' to connect the main clauses.
This satisfies standard English punctuation rules for both coordinate adjectives and compound independent clauses.

Anahtar Kavram

Commas with Coordinate Adjectives and Independent Clauses
Tahmini Süre:1m 0s
Soru 5295Soru

In right triangle UVWUVW, the right angle is located at vertex VV. The length of hypotenuse UWUW is 8585 centimeters. If sin(U)=1517\sin(U) = \frac{15}{17}, what is the length, in centimeters, of leg UVUV?

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Cevap: 4040

Cevap

The length of leg UVUV is 4040 centimeters.
By definition, sin(U)=oppositehypotenuse=VWUW\sin(U) = \frac{\text{opposite}}{\text{hypotenuse}} = \frac{VW}{UW}. Given sin(U)=1517\sin(U) = \frac{15}{17} and UW=85UW = 85, the opposite leg VW=85×1517=75VW = 85 \times \frac{15}{17} = 75 cm. Using the Pythagorean theorem UV2=UW2VW2=852752=72255625=1600UV^2 = UW^2 - VW^2 = 85^2 - 75^2 = 7225 - 5625 = 1600, we get UV=40UV = 40 cm. Alternatively, using cos(U)=1sin2(U)=817\cos(U) = \sqrt{1 - \sin^2(U)} = \frac{8}{17}, the adjacent leg UV=85×817=40UV = 85 \times \frac{8}{17} = 40 cm.

Adım Adım Çözüm

1
Identify the relationship between sin(U)\sin(U) and the sides of right triangle UVWUVW.
sin(U)=oppositehypotenuse=VWUW=1517\sin(U) = \frac{\text{opposite}}{\text{hypotenuse}} = \frac{VW}{UW} = \frac{15}{17}.
By SOHCAHTOA, sine is the ratio of the opposite leg to the hypotenuse.
2
Calculate the length of the opposite leg VWVW.
VW=85×1517=75VW = 85 \times \frac{15}{17} = 75 centimeters.
Multiply the hypotenuse length UW=85UW = 85 by the sine ratio 1517\frac{15}{17}.
3
Apply the Pythagorean theorem (UV2+VW2=UW2UV^2 + VW^2 = UW^2) to solve for adjacent leg UVUV.
UV2+752=852    UV2+5625=7225    UV2=1600    UV=40UV^2 + 75^2 = 85^2 \implies UV^2 + 5625 = 7225 \implies UV^2 = 1600 \implies UV = 40 centimeters.
The square of the hypotenuse equals the sum of the squares of the two legs.

Anahtar Kavram

Right Triangle Trigonometry (SOHCAHTOA) and Pythagorean Relationship
Tahmini Süre:1m 30s
Soru 5296Soru

A specialty coffee roasting facility packages a batch of cc pounds of dark roast coffee beans into retail bags. Each bag is filled with exactly 1.51.5 pounds of coffee. If the facility completely fills 2828 bags with no coffee left over, which of the following equations can be used to find the total weight, cc, in pounds, of the coffee batch?

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Cevap: c1.5=28\frac{c}{1.5} = 28

Cevap

The equation that can be used to find the total weight is c1.5=28\frac{c}{1.5} = 28.
To find the number of bags filled, the total weight of coffee (cc) must be divided into equal parts of 1.51.5 pounds each. Setting this quotient equal to the total number of filled bags (2828) gives the equation c1.5=28\frac{c}{1.5} = 28.

Adım Adım Çözüm

1
Identify the given quantities and unknown variable
Total weight = cc pounds; Weight per bag = 1.51.5 pounds; Total number of bags = 2828.
Establishing clear variable definitions is necessary before setting up an algebraic model.
2
Formulate the relationship between total quantity, unit rate, and total items
Total WeightWeight per Bag=Total Number of Bags\frac{\text{Total Weight}}{\text{Weight per Bag}} = \text{Total Number of Bags}
Dividing a total quantity by the capacity of one container gives the total number of containers filled.
3
Substitute the known values and variable into the relationship formula
c1.5=28\frac{c}{1.5} = 28
This yields the correct one-step linear equation representing the scenario.

Anahtar Kavram

Writing one-step linear equations from word problems involving rates and equal grouping
Tahmini Süre:1m 0s
Soru 5297Soru

A circle in the standard (x,y)(x, y) coordinate plane is described by the equation x2+y26x+10y+18=0x^2 + y^2 - 6x + 10y + 18 = 0. A second circle is concentric with the first circle (meaning they share the exact same center) but has an area that is 44 times the area of the first circle. Which of the following is an equation of the second circle?

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Cevap: (x3)2+(y+5)2=64(x - 3)^2 + (y + 5)^2 = 64

Cevap

The equation of the second circle is (x3)2+(y+5)2=64(x - 3)^2 + (y + 5)^2 = 64.
Completing the square on x2+y26x+10y+18=0x^2 + y^2 - 6x + 10y + 18 = 0 yields (x3)2+(y+5)2=16(x - 3)^2 + (y + 5)^2 = 16, identifying the center as (3,5)(3, -5) and r12=16r_1^2 = 16. Concentric circles share the center (3,5)(3, -5). Quadrupling the area means the new area is 4×16π=64π4 \times 16\pi = 64\pi, so r22=64r_2^2 = 64. Plugging the center and new r2r^2 into the standard equation gives (x3)2+(y+5)2=64(x - 3)^2 + (y + 5)^2 = 64.

Adım Adım Çözüm

1
Convert the given circle equation to standard form by completing the square for both xx and yy.
Rearranging terms: (x26x)+(y2+10y)=18(x^2 - 6x) + (y^2 + 10y) = -18.
Adding (6/2)2=9( -6/2 )^2 = 9 and (10/2)2=25( 10/2 )^2 = 25 to both sides yields:
(x3)2+(y+5)2=18+9+25=16(x - 3)^2 + (y + 5)^2 = -18 + 9 + 25 = 16.
Standard form (xh)2+(yk)2=r2(x - h)^2 + (y - k)^2 = r^2 reveals the center (h,k)(h, k) and squared radius r2r^2.
2
Identify the center and radius of the original circle.
Center = (3,5)(3, -5) and radius squared r12=16r_1^2 = 16 (so r1=4r_1 = 4).
Concentric circles share the exact same center (h,k)=(3,5)(h, k) = (3, -5).
3
Determine the radius squared of the second circle based on the area constraint.
The area of a circle is A=πr2A = \pi r^2. Since A2=4A1A_2 = 4 A_1, we have πr22=4(πr12)    r22=4r12=4(16)=64\pi r_2^2 = 4 (\pi r_1^2) \implies r_2^2 = 4 r_1^2 = 4(16) = 64.
Quadrupling the area quadruples the value of r2r^2.
4
Write the standard form equation for the second circle using center (3,5)(3, -5) and r22=64r_2^2 = 64.
(x3)2+(y+5)2=64(x - 3)^2 + (y + 5)^2 = 64.
Substituting h=3h = 3, k=5k = -5, and r22=64r_2^2 = 64 into (xh)2+(yk)2=r22(x - h)^2 + (y - k)^2 = r_2^2.

Anahtar Kavram

Standard form of a circle equation (xh)2+(yk)2=r2(x - h)^2 + (y - k)^2 = r^2 and area relationship A=πr2A = \pi r^2
Soru 5298Soru

A security code consists of four characters generated in order: a letter, a digit, a letter, and a digit.

- The 1st character is a letter chosen from the 5-element set {A,B,C,D,E}\{A, B, C, D, E\}.
- The 2nd character is a digit chosen from the 9 non-zero digits {1,2,3,4,5,6,7,8,9}\{1, 2, 3, 4, 5, 6, 7, 8, 9\}.
- The 3rd character is a letter chosen from {A,B,C,D,E}\{A, B, C, D, E\}, but it cannot be the same as the 1st character.
- The 4th character is an even digit chosen from {2,4,6,8}\{2, 4, 6, 8\}, but it cannot be the same as the 2nd character.

How many different security codes can be formed following these rules?

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Cevap: 640

Cevap

640
The problem requires counting combinations with dependent restrictions, which can be solved by splitting into two mutually exclusive cases. If the 2nd character is an odd digit (5 possibilities), the 4th character has all 4 even digits available, giving 5 × 5 × 4 × 4 = 400 valid codes. If the 2nd character is an even digit (4 possibilities), the 4th character cannot match it, leaving 3 options, giving 5 × 4 × 4 × 3 = 240 valid codes. Summing the two distinct cases gives 400 + 240 = 640.

Adım Adım Çözüm

1
Analyze the conditions for the digit positions (2nd and 4th characters).
The restrictions require dividing the counting into two cases based on the parity of the 2nd character.
The 4th character must be chosen from the 4 even digits {2, 4, 6, 8}. If the 2nd character is an odd digit, it does not reduce the choices for the 4th character. If the 2nd character is an even digit, it reduces the remaining choices for the 4th character from 4 to 3.
2
Calculate total possibilities for Case 1 (2nd character is odd).
5 × 5 × 4 × 4 = 400 codes.
There are 5 options for the 1st letter, 5 odd digits {1, 3, 5, 7, 9} for the 2nd character, 4 remaining letters for the 3rd character, and 4 even digits for the 4th character.
3
Calculate total possibilities for Case 2 (2nd character is even).
5 × 4 × 4 × 3 = 240 codes.
There are 5 options for the 1st letter, 4 even digits {2, 4, 6, 8} for the 2nd character, 4 remaining letters for the 3rd character, and 3 remaining even digits for the 4th character.
4
Sum the results of the two cases.
400 + 240 = 640 security codes.
According to the Addition Principle of counting, the total number of outcomes for mutually exclusive events is the sum of their individual outcomes.

Anahtar Kavram

Fundamental Counting Principle with Case Analysis
Soru 5299Soru

A biology student recorded the mass, in grams, of 6 plant specimens after three weeks of growth: 1414, 99, 2222, 1818, 1212, and 1515. If a 7th plant specimen is added to the data set, what must its mass be, in grams, so that the mean mass of all 7 specimens equals the median mass of the original 6 specimens?

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Cevap: 11.511.5

Cevap

The mass of the 7th specimen must be 11.5 grams.
To find the required mass of the 7th specimen, first order the original 6 data points from least to greatest: 9,12,14,15,18,229, 12, 14, 15, 18, 22. The median is the average of the two middle values, 14 and 15, which gives 14+152=14.5\frac{14 + 15}{2} = 14.5 grams. The problem states that the mean of all 7 specimens must equal 14.5 grams. The sum of 7 values with a mean of 14.5 is 7×14.5=101.57 \times 14.5 = 101.5 grams. Since the sum of the first 6 specimens is 9+12+14+15+18+22=909 + 12 + 14 + 15 + 18 + 22 = 90 grams, the mass of the 7th specimen must be 101.590=11.5101.5 - 90 = 11.5 grams.

Adım Adım Çözüm

1
Sort the original data set to find its median.
The sorted list of masses is 9,12,14,15,18,229, 12, 14, 15, 18, 22.
Finding the median of a data set requires placing the numbers in ascending order.
2
Calculate the median of the original 6 specimens.
Median=14+152=14.5 grams\text{Median} = \frac{14 + 15}{2} = 14.5\text{ grams}.
For an even number of values, the median is the average of the two middle terms.
3
Determine the required total mass of all 7 specimens.
Required Total Mass=7×14.5=101.5 grams\text{Required Total Mass} = 7 \times 14.5 = 101.5\text{ grams}.
Mean is calculated by dividing total sum by count, so Total Sum=Mean×Count\text{Total Sum} = \text{Mean} \times \text{Count}.
4
Calculate the sum of the original 6 specimens.
Original Sum=9+12+14+15+18+22=90 grams\text{Original Sum} = 9 + 12 + 14 + 15 + 18 + 22 = 90\text{ grams}.
Summing the existing measurements allows us to find the missing amount.
5
Subtract the original sum from the required total sum.
Mass of 7th Specimen=101.590=11.5 grams\text{Mass of 7th Specimen} = 101.5 - 90 = 11.5\text{ grams}.
The difference between the required total sum and the current total sum gives the value of the new addition.

Anahtar Kavram

Descriptive Statistics: Finding a missing data value given a target mean based on a sample median.
Tahmini Süre:1m 15s
Soru 5300Soru

A commercial printing press produces 420420 color brochures every 1515 minutes. If the press operates continuously at this constant rate, how many hours will it take to produce a total of 5,0405,040 brochures?

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Cevap: 33

Cevap

3 hours
The correct answer is 3 hours because the printing press produces 28 brochures per minute (420÷15420 \div 15). In one hour (60 minutes), it produces 1,680 brochures (28×6028 \times 60). To complete 5,040 brochures, it takes 5,040÷1,680=35,040 \div 1,680 = 3 hours.

Adım Adım Çözüm

1
Determine the unit rate per minute.
420 brochures÷15 minutes=28 brochures per minute420 \text{ brochures} \div 15 \text{ minutes} = 28 \text{ brochures per minute}.
Finding the unit rate simplifies conversion to hourly production.
2
Convert the unit rate to an hourly rate.
28 brochures/minute×60 minutes/hour=1,680 brochures per hour28 \text{ brochures/minute} \times 60 \text{ minutes/hour} = 1,680 \text{ brochures per hour}.
The question asks for the total time in hours.
3
Calculate the total hours needed to print 5,040 brochures.
5,040 brochures÷1,680 brochures/hour=3 hours5,040 \text{ brochures} \div 1,680 \text{ brochures/hour} = 3 \text{ hours}.
Dividing total target quantity by hourly rate yields the required time.

Anahtar Kavram

Unit Rates and Multi-Step Proportional Reasoning
ÖncekiSayfa 265 / 278Sonraki
Tüm alıştırma soruları — ACT | Examkin