 # A box contains b red balls 2b white 3b blue balls \$ b>03 balls are selected without replacement if A is the event that no two of the selected balls have same colour then1) no value of b for which P(A)= 0.32) one value of b for which P(A)= 0.3 and this value is less than 103) two values of b and this value is greater than 104) None Badiuddin askIITians.ismu Expert
148 Points
12 years ago

Dear Mayank

3 balls are selected without replacement if  no two of the selected balls have same colour then

= bC1 * 2bC1 *3bC

Probability P =[ bC1 * 2bC1 *3bC]/6bC3

=6b2 /(6b-1)(6b-2)

for P = 0.3

6b2 /(6b-1)(6b-2)  =0.3

8b2 -9b +1 =0

b=1 and b =1/8

b can not be 1/8

so only one value of b =1

option b is correct

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