For her birthday, Monica can invite 6 of her 15 student friends to join her at a theme park. If she chooses to invite friends at random, what is the probability that friends Tessa, Guido, Brendan, Faith, Charlotte and Rhianna are chosen?
10 out of 27,358
1 out of 5,005
1 out of 720
1 out of 3,603,600

B. 1 out of 5,005

Step-by-step explanation:

Given

Number of Friends = 15

Required

Probability of selecting 6 friends

The first step is to calculate the number of ways 6 friends can be selected

The keyword in the above statement is selection;

This implies combination;

The number of ways is calculated as follows;

Where n = 15 and r = 6

becomes

Hence, there are 5005 ways of selecting 6 from 15 friends

Since, there's only one way of selecting the 6 named friends

Then, the probability is 1 out of 5,005