Question

A drawer contains eight socks (eight total, not eight pairs[which would be 16 socks total]), 2 are white, 1 is black, 3 are red, 1 is blue, and the last one is yellow.

1. What is the probability of choosing a white sock, a black sock and a red sock in three draws?

2. What is the probability of choosing a red sock first, and a black and a white sock, does not matter the order for the last two?

3. What is the probability of choosing a black sock first followed by a blue sock and a yellow sock last?

4. What is the probability of choosing either a red sock or a white sock or a black sock or blue sock or a yellow sock in a single draw?

Answer 1

1. What is the probability of choosing a white sock, a black sock and a red sock in three draws?

(3!/(1!*1!*1!)*(2/8)*(1/8)*(3/8) = 9/128

2. What is the probability of choosing a red sock first, and a black and a white sock, does not matter the order for the last two?

(3/8)*(2/8)*(1/8)+(3/8)*(1/8)*(2/8) = 3/128

3. What is the probability of choosing a black sock first followed by a blue sock and a yellow sock last?

(1/8)*(1/8)*(1/8) = 1/512

4. What is the probability of choosing either a red sock or a white sock or a black sock or blue sock or a yellow sock in a single draw?

1