Homework SourseA company surveyed 1000 people on their age and the number o
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.
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?
(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?
| Jeans Purchased Annually | |||||
|---|---|---|---|---|---|
| 0 | 1 | 2 | 3 or More | Total | |
| Under 12 | 0 | 70 | 79 | 41 | 190 |
| 12-18 | 28 | 88 | 110 | 64 | 290 |
| 19-25 | 39 | 76 | 110 | 75 | 300 |
| over 25 | 69 | 51 | 79 | 21 | 220 |
| Total | 136 | 285 | 378 | 201 | 1000 |
Solution
a)
There are 110+110+79 = 299 people who are over 18 and purchases 2 jeans annually.
There are 290+300+220 = 810 people who are over 18.
Thus,
P(2 jeans|over 18) = 299/810 = 0.369135802 [answer]
***********
b)
There are 136 + 285+378 = 799 people who purchased less than 3 pairs of jeans.
Of those, ther are 28+88+110 = 226 who are 12-18 y/o.
Thus,
P(12-18|less than 3) = 226/799 = 0.282853567 [ANSWER]
