BL602 - Homework #2

Management at Double Down wants to estimate the average amount spent on meals at their drive-through with a margin of error of no more than $1.00 ($0.50 in either direction), 90% of the time.

Question 1

1. If the mean in their sample was $14.22 and the standard deviation was $4.12, how big does their sample need to be?

Question 2

Assume that the sufficiently large sample from part

a) is collected and data is clearly bi-modal (below). Comment and reason