A population has standard deviation 20. For a random sample of 25 observations, what is the standard deviation of the sampling distribution of the sample mean?
Correct answer: B. 4
- A. 0.8
- B. 4
- C. 5
- D. 20
Explanation
The standard error of the sample mean is σ divided by the square root of n. Thus, it is 20/√25 = 20/5 = 4.
Report an error
The more specific you are, the faster it gets fixed. A source beats an opinion.
Prefer email? support@testustad.com
Practise Probability and Probability Distributions
30 free Probability and Probability Distributions MCQs from Quantitative Methods, each with the correct answer and an explanation. Unlimited attempts, no account needed.
Exams that ask Quantitative Methods questions like this
Quantitative Methods is on this paper prepared for on TestUstad, and all of them draw the same bank, so this question is worth knowing for it.
More Probability and Probability Distributions questions
For a continuous random variable with a probability density function, what is the probability of taking one exact specified value?
A normal random variable has mean 50 and standard deviation 10. What is its standardized value when X = 70?
A continuous random variable is uniformly distributed on the interval from 2 to 8. What is the probability that it lies between 3 and 5?
Two cards are drawn successively without replacement from a standard 52-card deck. What is the probability that both cards are aces?
If X follows a binomial distribution with n = 10 and p = 0.4, what is Var(X)?
If X follows a Poisson distribution with parameter λ = 2, what is P(X = 2)?