(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A. Mrs. Moyer’s class has to choose 4 out of 12 people to serve on an activity

committee.

B. The four chosen students are then selected for the positions of chairperson, activities

planner, activity leader, and treasurer.

What is the probability that any one of the students is chosen to be the

chairperson?

2. Relevant equations

Permutations and combinations

3. The attempt at a solution

I first calculated the number of outcomes for part A: 12!/((12-4)!4!)=495. Then I calculated the number of outcomes for part B: 4!=24. Which gives the total number of outcomes: 495*24=11880.

After that, I calculated the favorable number of outcomes for A and B:

A: (1*11*10*9)/3!=165

B: 1*3*2*1=6

Which gives the total number of outcomes: 165*6=990.

Therefore, the probality is 990/11880 or 1/12.

The problem is that the book says it's 1/2970.

Who's right?

Thanks in advance,

Shawn

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# Homework Help: Probability: me vs. textbook

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