SOLUTION: a bag contains 12 red marbles, 5 yellow marbles, and 15 green marbles. how many additional red marbles must be added to the 32 marbles already in the bag so that the probability ra

Algebra ->  Probability-and-statistics -> SOLUTION: a bag contains 12 red marbles, 5 yellow marbles, and 15 green marbles. how many additional red marbles must be added to the 32 marbles already in the bag so that the probability ra      Log On


   

Question 368015: a bag contains 12 red marbles, 5 yellow marbles, and 15 green marbles. how many additional red marbles must be added to the 32 marbles already in the bag so that the probability randomly drawing a red is 3/5
A: 13
B: 18
C: 28
D: 32
E: 40
Answer by edjones(8007) About Me  (Show Source):
You can put this solution on YOUR website!
Let x=how many additional red marbles must be added
(x+12)/(x+32)=3/5
5(x+12)=3(x+32)
5x+60+3x+96
2x=36
x=18
.
Ed