We draw a simple random sample of 40 bills from a restaurant (representing 40 tables

served).The population is the set of 300 bills for the week.For each invoice, we

note:

X: the number of people served

Y: the amount of the invoice

We plan to take a sample next week to estimate certain parameters.We

assumes that the number of invoices will not have changed - it will remain 300

Determine the size of the sample that will need to be drawn so that the margin of error in the estimation of

total revenue for the week is 5%.You will estimate the necessary parameters from

your sample assuming these settings will not have changed by next week

Here is a summary of sample data: Number of persons Amount of served by invoice (X) invoice (Y) Sum 80 2,699.11 Corrected variance 1.47 1,876.84