Q.

Bag A contains 9 white and 8 black balls, while bag B contains 6 white and 4 black balls. One ball is randomly picked up from the bag B and mixed up with the balls in the bag A. Then a ball is randomly drawn from the bag A. If the probability, that the ball drawn is white, is pq, gcd (p,q) = 1, then p+q is equal to  [2026]

1 23  
2 24  
3 21  
4 22  

Ans.

(1)

[IMAGE 193]

 P(Drawn ball is white)=35×1018+25×918

                                                  =4890=815=pq

 p+q=23