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A box contains 40 pens out of which x a...

A box contains 40 pens out of which x are non-defective. If one pen is drawn at random, the probability of drawing a non defective pen is y. If we replace the pen drawn and then add 20 more non-defective pens in this bag, the probability of drawing a non-defective pen is 4y. Then, evaluate the value of x.

A

4

B

7

C

6

D

2

Text Solution

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The correct Answer is:
A
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