Question

There are 32 pieces of building blocks in a bag: 8 each of blue, green, red, and yellow. Four pieces are chosen at random. Identify the probability that all 4 of the pieces are red. A. 6/3596 B. 6/4356 C. 7/899 D. 7/3596

Answer 1

D. 7/3596

Explanation:

We have 8 red out of 32 total blocks

1st choice:

• probability of red= 8/32= 1/4

2nd choice, one removed and we have 7 red left out of 31 total blocks

• probability of red= 7/31

3rd choice, 2 removed and we have 6 red left out of 30 total blocks

• probability of red= 6/30= 1/5

4th choice, 3 removed and we have 5 red left out of 29 total blocks

• probability of red= 5/29

Now, the probability of getting 4 red blocks is:

• 1/4*7/31*1/5*5/29= 7/3596

Correct answer choice is the last one