Question

1. Anita plans to give her husband 4 shirts for his birthday. She narrows the search to 4 shirts from a selection of 15 shirts at Dillon's Store or 4 from a selection of 20 shirts at The Men's Shop. In how many ways can she select the shirts

Answer 1

6210

Explanation:

This is simple problem of section of few things from a lot.

`A_(1)`: selection of 4 shirts from 15 shirts

`A_(2)`: selection of 4 shirts from 20 shirts

`A_(1)` =
`\binom{15}{4}= (15!)/(4!*11!)`

=1365

`A_(2)` =
`\binom{20}{4}= (20!)/(4!*16!)`

=4845

so the number of ways in which she can select shirts

= 1365+4845= 6210