A bag contains 4 white balls and some red balls. If the probability of

1.	A bag contains 4 white balls and some red balls. If the probability of drawing a white ball from the bag is \(\frac{2}{5},\) find the number of red balls in the bag.
Answer» Let the number of red ball be x. total number of red balls = 4 + x. probability of drawing a white ball is = \(\frac{2}{5}\) \(\therefore \frac{4}{4+x}=\frac{2}{5}\) 2(4 + x) = 4 × 5 4 + x = 2 × 5 = 10 X = 10 - 4 = 6 X = 6 Thus the number of red balls are 6.

A bag contains 4 white balls and some red balls. If the probability of drawing a white ball from the bag is \(\frac{2}{5},\) find the number of red balls in the bag.

Answer»

Let the number of red ball be x.

total number of red balls = 4 + x.

probability of drawing a white ball is = \(\frac{2}{5}\)

\(\therefore \frac{4}{4+x}=\frac{2}{5}\)

2(4 + x) = 4 × 5

4 + x = 2 × 5 = 10

X = 10 - 4 = 6

X = 6

Thus the number of red balls are 6.

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A bag contains 4 white balls and some red balls. If the probability of drawing a white ball from the bag is \(\frac{2}{5},\) find the number of red balls in the bag.

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