Question

A company surveyed 1000 people on their age and the number of jeans purchased annually. The results of the poll are shown in the table. Jeans Purchased Annually 0 1 2 3 or More Total Under 12 0 65 68 87 220 12-18 21 74 126 69 290 19-25 31 56 119 74 280 over 25 49 55 95 11 210 Total 101 250 408 241 1000 A person is selected at random. Use the table to answer these questions. Round your answers to three decimal places. (a) What is the probability that the person, who is over 18, purchases 2 pairs of jeans annually? Incorrect: Your answer is incorrect. (b) What is the probability that a person who purchased less than 3 pairs of jeans each year will be in the age group 12-18? Incorrect: Your answer is incorrect.

Answer 1

a) 0.437; b) 0.291

Explanation:

For part a,

There are 280+210 = 490 people that are over 18 years old. Out of these, 119+95 = 214 purchase 2 pairs of jeans annually. This is

214/490 ≈ 0.437

For part b,

There are 87+69+74+11 = 241 people who purchase 3 or more pairs of jeans. There were a total of 220+290+280+210 = 1000 people; this means there were 759 people tho purchased fewer than 3 pairs of jeans.

Out of these, 21+74+126 = 221 were in the age group 12-18. This gives us

221/759 ≈ 0.291