Question

A bag contains whte red black balls tw balls are taken at randm find the probabilty that both are white

Answer 1

Answer:

Open in app

The probability of drawing a black ball on the first draw is 10/20 or .5. If the draws are with replacement, then the probability of drawing a black ball on the second draw remains 10/20 or .5. The probability of drawing two black balls is .5 x .5 = .25. If the balls are drawn without replacement then the probability of drawing a black ball on the second draw is 9/20 or .45 and the probability of drawing two black balls is .5 x .45 = .225.

Answer 2

Answer:

yC2 / ((x+y+z)C2

Step-by-step explanation:

let there be x white balls, y red balls and z black balls

so....total possible cases

(x+y+z)C2

required cases

yC2

therefore....probability

yC2 / ((x+y+z)C2

(where C is combination)