a bag contains 18 ball out of which X balls are red if one ball is drawn at random from the bag what is the probability that it is not read and if two more red ball are put in the bag the probability of drawing a red ball between 9 upon a time to the probability of drawing a red ball in the first case find the value of x
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Total No . of Obs = 18
No . of Red Balls = x
Probability of Red Ball = Favourable Obs / Total No. of Obs
P(of Red Ball) = x/18
Two Red Balls Are Added
So,
No . of Red Balls = x + 2
Total no .of Balls = 18 + 2 = 20
P(of red Ball) = x + 2 / 20
P given 9 times of P obtained in A
9/8 * x/18 = (x + 2)/20
x / 16 = (x + 2)/20
(x / 16) * 20 = x + 2
5x / 4 = x + 2
5x = 4x + 8
5x - 4x = 8
x = 8
Therefore,
Initial No.Of Red Balls = 8
MARK AS BRAINILY PLEASE
No . of Red Balls = x
Probability of Red Ball = Favourable Obs / Total No. of Obs
P(of Red Ball) = x/18
Two Red Balls Are Added
So,
No . of Red Balls = x + 2
Total no .of Balls = 18 + 2 = 20
P(of red Ball) = x + 2 / 20
P given 9 times of P obtained in A
9/8 * x/18 = (x + 2)/20
x / 16 = (x + 2)/20
(x / 16) * 20 = x + 2
5x / 4 = x + 2
5x = 4x + 8
5x - 4x = 8
x = 8
Therefore,
Initial No.Of Red Balls = 8
MARK AS BRAINILY PLEASE
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