Bunuel wrote:

A committee of 2 people is to be selected out of 3 teachers and 4 preachers. If the committee is selected at random, what is the probability that the committee will be composed of at least 1 preacher?

A. 1/4

B. 1/3

C. 2/3

D. 6/7

E. 8/9

To determine how many ways to select at least one preacher, we can use the formula:

Number of ways to select at least 1 preacher = total number of ways to select the group - number of ways to select NO preachers

Total number of ways to select the group is:

7C2 = 7!/[2!(7-2)!] = (7 x 6)/2! = 21

The number of ways to select NO preachers is:

3C2 = (3 x 2)/2! = 3

Thus, the number of ways to select at least 1 preacher is 21 - 3 = 18 ways.

So the probability that the committee will be composed of at least 1 preacher is 18/21 = 6/7.

Answer: D

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Founder and CEO

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