Nokea
A closet is filled with red, blue, and green shirts. If 1/4 of the shirts are green and 1/3 are red, what fraction of the shirts are blue?
- A. 1/2
- B. 1/3
- C. 5/12
- D. 1/4
Correct Answer: C
Rationale: Let the total number of shirts be x. Given that 1/4 of the shirts are green and 1/3 are red, we have Green = x/4 and Red = x/3. To find the fraction of blue shirts, we subtract the fractions of green and red shirts from 1: Blue fraction = 1 - (1/4 + 1/3) = 1 - (3/12 + 4/12) = 1 - 7/12 = 5/12. Therefore, the fraction of blue shirts is 5/12. Choices A, B, and D are incorrect because they do not accurately represent the fraction of blue shirts given the information provided.
You may also like to solve these questions
If Mom's car drove 72 miles in 90 minutes, how fast did she drive in feet per second?
- A. 0.8 feet per second
- B. 48.9 feet per second
- C. 0.009 feet per second
- D. 70.4 feet per second
Correct Answer: D
Rationale: To convert miles per hour to feet per second, first convert time to hours: 90 minutes = 1.5 hours. Then, calculate the speed in miles per hour: 72 miles in 1.5 hours = 48 mph. Finally, convert mph to feet per second using the conversion factor 1 mph = 1.47 feet per second: 48 mph * 1.47 = 70.4 feet per second. Therefore, the correct answer is 70.4 feet per second. Choices A, B, and C are incorrect because they do not reflect the correct conversion from miles per hour to feet per second.
How will 0.80 be written as a percent?
- A. 40%
- B. 125%
- C. 90%
- D. 80%
Correct Answer: D
Rationale: To convert a decimal to a percent, you multiply by 100. Therefore, 0.80 * 100 = 80%. The correct answer is D. Choice A (40%) is incorrect as 0.80 is not equivalent to 40%. Choice B (125%) is incorrect as it is greater than 100%. Choice C (90%) is incorrect as it does not reflect the correct conversion of 0.80 to a percent.
When rounding 245.2678 to the nearest thousandth, which place value would be used to decide whether to round up or round down?
- A. Ten-thousandths
- B. Thousandths
- C. Hundredths
- D. Thousand
Correct Answer: A
Rationale: When rounding a number to the nearest thousandth, you look at the digit in the ten-thousandths place to determine whether to round up or down the digit in the thousandths place. In this case, rounding 245.2678 to the nearest thousandth, the digit in the ten-thousandths place is 6, which is greater than or equal to 5, so you would round up the digit in the thousandths place. Therefore, the correct answer is the ten-thousandths place. Choices B, C, and D are incorrect because they do not directly influence the rounding of the thousandths place in this scenario.
Which of the following equations does not represent a function?
- A. y = x^2
- B. y = sqrt(x)
- C. x = y^2
- D. y = 2x + 1
Correct Answer: C
Rationale: An equation represents a function if each input (x-value) corresponds to exactly one output (y-value). In the equation x = y^2, for a single x-value, there are two possible y-values (positive and negative square root), violating the definition of a function. This violates the vertical line test, where a vertical line intersects the graph in more than one point for non-functions. Choices A, B, and D all pass the vertical line test and represent functions, making them incorrect answers.
The phone bill is calculated each month using the equation C = 50 + 75D. The cost of the phone bill per month is represented by C, and D represents the gigabytes of data used that month. What is the value and interpretation of the slope of this equation?
- A. 75 dollars per gigabyte
- B. 75 gigabytes per day
- C. 50 dollars per day
- D. 50 dollars per gigabyte
Correct Answer: A
Rationale: The slope of the equation C = 50 + 75D is 75. This means that for each additional gigabyte used (represented by D), the cost (represented by C) increases by 75 dollars. Therefore, the correct interpretation of the slope is that it is 75 dollars per gigabyte. Choice B, 75 gigabytes per day, is incorrect as the slope does not represent the rate of data usage per day. Choice C, 50 dollars per day, is incorrect as it does not reflect the relationship between gigabytes used and the cost. Choice D, 50 dollars per gigabyte, is incorrect as it does not match the slope value of 75 in the equation.