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There are 5 white balls and 4 black balls in a bag. Second bag contains 7 white balls and 9 black balls. one ball is transferred from first bag to second. a single ball is taken out from second bag. What is the probability that the ball is white.
Read Solution (Total 7)
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- lets divide this into 2 cases
case 1:When a black ball is transferred from bag 1 to 2
(4/9)*(7/17)=28/153
case 2: When a white ball is transferred from bag 1 to 2
(5/9)*(8/17)=40/153
total probability=(28/153)+(40/153)=4/9 - 10 years agoHelpfull: Yes(70) No(21)
- case 1: if white ball is transfered from first bag to second bag then, second bag will have 8W & 9B balls : 8/17
case 2: if black ball is transfered from first bag to second bag then, second bag will have 7W & 10B balls : 7/17
therefore, req prob = (8/17) + (7/17) = 15/17 - 10 years agoHelpfull: Yes(25) No(15)
- case1: white ball transffered from first bag and white ball taken out from 2nd bag=5/9*8/17.
case2: black ball transferred from first bag and white ball taken out from 2nd bag=4/9*7/17.
therefore probability of getting white ball=5/9*8/17 + 4/9*7/17=4/9. - 9 years agoHelpfull: Yes(10) No(1)
- @Prem
for case 1: we multiply by 4/9 as 4/9 will be the probabilty of getting black ball from bag 1 and 7/17 will be the probability of getting a white ball from 2nd bag.And as these two events are independent
so probability of two independent events A and B occurring simultaneously will be P(A)*P(B)
for case 2:similarly if a white ball comes from bag 1 which is transferred to bag 2 so probability of this event=5/9 and now probability of getting white ball from bag 2=8/17
so (5/9)*(8/17) - 10 years agoHelpfull: Yes(5) No(1)
- If white ball is transfer then probability is 8/17 OR black ball is transfer then probability is 7/17;
so finally 8/17+7/17=15/17 answer. - 9 years agoHelpfull: Yes(1) No(2)
- plss xplain it
- 10 years agoHelpfull: Yes(0) No(0)
- ayush upadhaya plzz explain why we are multiplying 4/9 and 5/9 ....
- 10 years agoHelpfull: Yes(0) No(0)
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