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. What defines a composite number?

A. A number with only two factors
B. A number that is a fraction
C. A number with more than 2 factors
D. A number with exactly two factors

Correct answer: C

Rationale: A composite number is a positive integer greater than one that has more than two factors. Choice A is incorrect because a number with only two factors is a prime number. Choice B is incorrect as being a fraction does not define a composite number. Choice D is incorrect because a number with exactly two factors is a prime number, not a composite number.

3. Which of the following describes a real-world situation that could be modeled by?

A. Courtney charges a $12 fee plus $2 per hour to babysit. Kendra charges a $10 fee plus $5 per hour. Write an equation to find the number of hours for which the two charges are equal.
B. Courtney charges a $2 fee plus $12 per hour to babysit. Kendra charges a $5 fee plus $10 per hour. Write an equation to find the number of hours for which the two charges are equal.
C. Courtney charges a $12 fee plus $2 to babysit. Kendra charges a $10 fee plus $5 to babysit. Write an equation to find the number of hours for which the two charges are equal.
D. Courtney charges $10 plus $2 per hour to babysit. Kendra charges $12 plus $5 per hour. Write an equation to find the number of hours for which the two charges are equal.

Correct answer: A

Rationale: In the given situation, Courtney charges a $12 fee plus $2 per hour to babysit, represented by the equation: 12 + 2h where h is the number of hours. Kendra charges a $10 fee plus $5 per hour, represented by the equation: 10 + 5h. To find the number of hours for which the two charges are equal, we set the two equations equal to each other: 12 + 2h = 10 + 5h. Solving for h gives h = 2. This means that the charges are equal after 2 hours of babysitting. Choice B is incorrect because the fee and hourly rates for Courtney and Kendra are reversed, leading to an incorrect equation. Choices C and D are incorrect as they do not accurately represent the given scenario of fees and hourly rates for babysitting by Courtney and Kendra.

4. Over several years, a real estate agent sold houses, with one year having an outlier where she sold 11 houses. Which of the following measures will most accurately reflect the number of houses she sold per year?

A. mean
B. median
C. mode
D. range

Correct answer: B

Rationale: The outlier of 11 would skew the data if the mean or range were used. The median, however, is not affected by outliers and is the most appropriate measure for reflecting the number of houses she sold per year. In this scenario, the data set does not have a mode as each value occurs only once, making mode not the most appropriate choice.

5. What defines an integer?

A. A whole number (not a fraction or decimal!) that can be positive, negative, or zero
B. A number with a decimal point
C. A fraction
D. A percentage

Correct answer: A

Rationale: An integer is a whole number that can be positive, negative, or zero. It does not include fractions or decimals. Choice B, 'A number with a decimal point,' is incorrect because integers do not have decimal points. Choice C, 'A fraction,' is incorrect because integers are not expressed as ratios of two integers. Choice D, 'A percentage,' is incorrect because integers are not necessarily related to proportions out of 100.