Question

A group of 500,000 families has an average income of $37,000 and an SD of $20,000. Twenty percent of these families have an income over $50,000. We take a sample of 900 families to find the combined salary of 900 families. (i) How many tickets should be in the box? (ii) What should be on the tickets: 0’s and 1’s or the salary data (iii) How many draws do we take from the box. (iv) Find the chance that the combined salary is over $33,000,000. You may pretend that the draws are with replacement. (v) Find the chance that the average salary of the sample exceeds $45,000

Answer 1

Note: Z table is used to obtain the probabilities