In how many different ways can a ski club consisting of 20 people select a person for its officers? the positions available are president, vice president, treasurer, and secretary. no person can hold more than one positions and the each office is filled in order.
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a)74
b) 116,280
c) 1440
d) 4845

D. 4845ways

Step-by-step explanation:

Combination has to do with selection.

To select r object from pool of n objects, this can be expressed using the combination formula

nCr = n!/(n-r)!r!

According to the question, total number of people in the ski club is 20 i.e n=20

If the positions available are president, vice president, treasurer, and secretary, this shows that we need to select 4people to from the pool of 20 to fill the positions. This can be done in 20C4 number of ways.

20C4 = 20!/(20-4)!4!

20C4 = 20!/16!4!

20C4 = 20×19×18×17×16!/16!×4×3×2×1

20C4 = 20×19×18×17/24

20C4 = 4845

This can be done in 4845ways

your answer is the last one

step-by-step explanation:

divide the length of a'c' by the length of ac to get a scale factor of two

& then reflect vertically (over the y-axis)

so your answer is dilation by a scale factor of 2 followed by reflection over the y-axis