Question

In: Statistics and Probability

1. The mean amount of money that U.S adults spend on food in a week is...

1. The mean amount of money that U.S adults spend on food in a week is $140 and standard deviation is $42. Random samples of size 40 are drawn from this population and the mean of each sample is determined. a. Find the mean and standard deviation of the sampling distribution of sample means. b. What is the probability that the mean amount spent on food in a week for a certain sample is more than $143? c. What is the probability that the mean amount spent on food in a week for a certain sample is between $138 and $143?

Expert Solution

Q.1) Given that, mean = $140 and

standard deviation = $42

sample size ( n ) = 40

a) the mean and standard deviation of the sampling distribution of sample means are,

b) We want to find,

Therefore, required probability is 0.4404

c) We want to find,

Therefore, the required probability is 0.2853

orchestra answered 2 years ago

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