SOLUTION: A bag contains only red blocks, white blocks, and black blocks. The probability of selecting a red block is 1/5, and the probability of selecting a white block is 3/8. What is th

Algebra ->  Probability-and-statistics -> SOLUTION: A bag contains only red blocks, white blocks, and black blocks. The probability of selecting a red block is 1/5, and the probability of selecting a white block is 3/8. What is th      Log On


   

Question 329668: A bag contains only red blocks, white blocks, and black blocks. The probability
of selecting a red block is 1/5, and the probability of selecting a white
block is 3/8. What is the fewest number of black blocks that could be in
the bag?
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
Find a common denominator.
P%28R%29=R%2F%28R%2BW%2BB%29=1%2F5=8%2F40
P%28W%29=W%2F%28R%2BW%2BB%29=3%2F8=15%2F40
.
.
.
P%28R%29%2BP%28W%29%2BP%28B%29=1.0
.
.
.
8%2F40%2B15%2F40%2BP%28B%29=1
P%28B%29=%2840-8-15%29%2F40=17%2F40
.
.
.
17 black blocks would be the fewest.