Question

A ski patrol unit has nine members available for duty, and two of them are to be sent to rescue an injured skier. In how many ways can two of these nine members be selected? Enter you answer; In how many ways can two of these nine members be selected?

Answer 1

36

Explanation:

The number of two of the nine members of ski patrol unit can be chosen is equal to the combinations of 9 taken 2. This can be calculated using the formula:

`(9!)/(2!*(9-2)!)`

=
`(9!)/(2!*7!)`, where

9! =9×8×7×6×5×4×3×2×1 and

7!=7×6×5×4×3×2×1

2!=2×1 then the equation becomes:

=
`(9*8)/(2)` =36