SOLUTION: A box initially contained 30 chess pawns, all either black or white. The probability of drawing a white pawn was 2/5. Some more white pawns we’re added to the box so that the pro

Question 1141621: A box initially contained 30 chess pawns, all either black or white. The probability of drawing a white pawn was 2/5. Some more white pawns we’re added to the box so that the probability of picking out a white pawn was raised to 1/2. How many white pawns were added to the box ?
A)2
B)3
C)6
D)18
Answer by Boreal(15235) (Show Source): You can put this solution on YOUR website!
30 pawns with 2/5 probability of white means 12 were white
(12+x)/(30+x)=1/2
cross multiply and 15+(1/2)x=12+x
3=(1/2)x
x=6 pawns ANSWER
now there are 36 with 18 white.
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