In a jar there are balls in different colors: blue, red,

Question

In a jar there are balls in different colors: blue, red, green and yellow.
The probability of drawing a blue ball is 1/8.
The probability of drawing a red ball is 1/5.
The probability of drawing a green ball is 1/10.
If a jar cannot contain more than 50 balls, how many yellow balls are in the Jar?

a) 23.
b) 20.
c) 24.
d) 17.
e) 25.

walker · Answer

A 

8=2^3, 5, 10=2*5: ==> LCM (8,5,10)=2^3*5=40

py=1-5/40-8/40-4/40=23/40

N=23

LM · Answer

P(B) = 1/8

P(R) = 1/5

P(G) = 1/10

P(Y) = 1- (1/8 + 1/5 +1/10) = 23/40

Blue Balls = 5
Red= 8
Green =4
and Yellow = 23

Yeah LCM is 40 as walker mentioned in his post.

GMATBLACKBELT · Answer

Since we cant have a part of a ball, essentially x/8, x/5, x/10 = an integer. (x is the total amount of balls)

So from here all we have to do is find the LCM, which is 40.

R=8
B=5
G=4

40-17=23

A

In a jar there are balls in different colors: blue, red,

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