₈C₁ ways to choose 1 new camera from 8 new cameras
₆C₃ ways to choose 3 refurbished cameras from 8 refurbished cameras
₁₄C₄ ways to choose 4 cameras from 14 cameras
The probability is:
P = ₈C₁ ₆C₃ / ₁₄C₄
P = 8×20 / 1001
P = 160 / 1001
P ≈ 0.160
ii) At most one new camera means either one new camera or no new cameras. We already found the probability of one new camera. The probability of no new cameras is the same as the probability of choosing 4 refurbished cameras:
Since we are looking for the principal amount, then all we have to do is reverse the process of getting the amount of tax. In order to get the principal, you just have to divide 22 with 0.05. The answer is 440 so that is the principal amount you are looking for.
