The Retail Advertising and Marketing Association would like to estimate the average amount of money that a person spends for Mother's Day with a 99% confidence interval and a margin of error within plus or minus $6. Assuming the standard deviation for spending on Mother's Day is $36, the required sample size is . A) 313 B) 284 C) 210 D) 239

D) 239

Step-by-step explanation:

We have that to find our level, that is the subtraction of 1 by the confidence interval divided by 2. So:

Now, we have to find z in the Ztable as such z has a pvalue of .

So it is z with a pvalue of , so

Now, find the margin of error M as such

In which is the standard deviation of the population and n is the size of the sample.

Required sample size:

Is n

n is found when

We have that

So

Simplifying by 6

We round up, and the answer is 239.

10 you would take 50/ .2

step-by-step explanation:

i believe your answer is 99.7% of 7-year-old children are between 46.6 inches and 49.5 inches tall.