SOLUTION: Please help me solve this problem : A school's faith awareness group consists of 15 students and 3 teachers. If four members of the groups are randomly chosen to go to a retreat

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Question 1162381: Please help me solve this problem :
A school's faith awareness group consists of 15 students and 3 teachers. If four members of the groups are randomly chosen to go to a retreat, determine the probability of selecting three students.
Answer by greenestamps(13209) About Me  (Show Source):
You can put this solution on YOUR website!


The denominator of the probability fraction is the number of ways of choosing 4 of the 18 people: 18C4.

The numerator is the number of ways of choosing 3 of the 15 students AND 1 of the 3 teachers: (15C3) times (3C1).

P(3 students and 1 teacher) = %28%2815C3%29%2A%283C1%29%29%2F%2818C4%29

Use a calculator if necessary....

Leave the answer in decimal form only if an approximate answer is needed; leave it as a fraction if an exact answer is required.