when the sampling distribution of means is plotted which of the following is true

ATI TEAS 7

TEAS Test Math Prep

1. When the sampling distribution of means is plotted, which of the following is true?

A. The distribution is approximately normal.
B. The distribution is positively skewed.
C. The distribution is negatively skewed.
D. There is no predictable shape to the distribution.

Correct answer: A

Rationale: When the sampling distribution of means is plotted, the distribution tends to be approximately normal, especially as the sample size increases. This phenomenon is described by the Central Limit Theorem, which states that the sampling distribution of the sample mean will be normally distributed regardless of the shape of the original population distribution as long as the sample size is sufficiently large. Choices B and C are incorrect because sampling distributions of means are not skewed. Choice D is incorrect because there is a predictable shape to the distribution, which is approximately normal.

2. A car travels 60 miles in 1 hour. How long will it take to travel 180 miles at the same speed?

A. 3 hours
B. 4 hours
C. 2.5 hours
D. 5 hours

Correct answer: A

Rationale: To find the time needed to travel 180 miles at the same speed of 60 miles per hour, you divide the total distance by the speed. 180 miles ÷ 60 mph = 3 hours. Therefore, it will take 3 hours to travel 180 miles at the given speed. Choice B, 4 hours, is incorrect as it does not align with the calculation. Choice C, 2.5 hours, is incorrect as it underestimates the time needed for the distance. Choice D, 5 hours, is incorrect as it overestimates the time required based on the given speed.

3. Which of the following percentages is equivalent to 5 ¼?

A. 525%
B. 514%
C. 5.25%
D. 5.14%

Correct answer: A

Rationale: To convert a mixed number to a decimal, 5 ¼ becomes 5.25. To convert this decimal to a percentage, you multiply it by 100. Therefore, 5.25 × 100 = 525%. Choice A is correct. Choice B (514%) is incorrect as it does not match the equivalent of 5 ¼. Choice C (5.25%) is the decimal equivalent of 5 ¼, not the percentage. Choice D (5.14%) is a different value and does not represent the percentage equivalent of 5 ¼.

4. What is the result of (4.71 × 10^3) - (2.98 × 10^2)? Which of the following is the correct simplified expression?

A. 1.73 × 10
B. 4.412 × 10^2
C. 1.73 × 10^3
D. 4.412 × 10^3

Correct answer: D

Rationale: The correct answer is D: 4.412 × 10^3. To simplify the expression, rewrite 4.71 × 10^3 as 47.1 × 10^2. Subtract the values in front of 10^2: 47.1 - 2.98 = 44.12. Rewriting this gives 44.12 × 10^2 = 4.412 × 10^3. Choice A is incorrect as it does not account for the correct subtraction result. Choice B is incorrect as it does not correctly simplify the expression. Choice C is incorrect as it provides an incorrect power of 10 in the simplified expression.

5. Express 18/5 as a reduced mixed number.

A. 3 3/5
B. 3 1/15
C. 3 1/18
D. 3 1/54

Correct answer: A

Rationale: To convert the improper fraction 18/5 to a mixed number, divide 18 by 5. The quotient is 3 with a remainder of 3, which translates to 3 3/5. Therefore, the correct answer is A. Choices B, C, and D are incorrect because they do not accurately represent the conversion of 18/5 to a mixed number.