From a group of 8 volunteers, including andrew and karen, 4 people are to be selected at random to organize a charity event. what is the probability that andrew will be among the 4 volunteers selected and karen will not?

The probability that Andrew will be among the 4 volunteers selected and Karen will not is 2/7.

Step-by-step explanation:

From the given information it is clear that

The total number of volunteers, including Andrew and Karen = 8

The total number of volunteers, excluding Andrew and Karen = 8-2 = 6

We need to find the probability that Andrew will be among the 4 volunteers selected and Karen will not.

Total number of ways of selecting r volunteers from n volunteers is

Total number of ways of selecting 4 volunteers from 8 volunteers is

Total number of ways of selecting 4 volunteers from 8 volunteers, so that Andrew will be among the 4 volunteers selected and Karen will not is

The probability that Andrew will be among the 4 volunteers selected and Karen will not is

Therefore the probability that Andrew will be among the 4 volunteers selected and Karen will not is 2/7.

341

step-by-step explanation:

all you have to do is 9x31 (which equals 279) and then 20x31 (which equals 620). then you have to subtract. 620-279=341.