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1. There are 4 baskets. The first basket has 3 apples and 4 oranges, the second one has 4 apples and 5 mangoes, the third one has 6 Mangoes and 2 bananas and the last one has 7 bananas and 2 apples. If a fruit is randomly chosen from any basket and it comes out to be an apple, then what is the probability that it was taken out from the second basket?
Read Solution (Total 11)
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- P(A|1)=3/7
P(A|2)=4/9
P(A|3)=0/8
P(A|4)=2/9
Hence event 1,2,3,4 are the partitions of the sample space.
The probability of choosing an apple, by the law of total probability
P(A)=P(A|1)P(1)+P(A|2)P(2)+P(A|3)P(3)+P(A|4)P(4)
=3/7*1/4+4/9*1/4+0/8*1/4+2/9*1/4
=23/84
By Baye's theorem,
P(2|A)=P(A|2)*P(2)/P(A)
=4/9*(1/4)/(23/84)
=28/69 - 9 years agoHelpfull: Yes(27) No(2)
- probability of choosing 2 nd basket is 1/4 (1 among 4 baskets)
second basket has 4 apples and total fruits 4 A+5 M =9
taking apple out is 4/9
so ans is 1/4 * 4 /9 =1/9 - 9 years agoHelpfull: Yes(25) No(15)
- the probability of selecting a basket is 1/4.
the probability of selecting an apple from basket 2 is 4c1/9c1*1/4.
now the probability of selecting an apple from any of the baskets is given by 1/4*3/7+4/9*1/4+1/4*0/8+1/4*2/9.
finally p(apple from basket 2 )=( 4c1/9c1*1/4)/(1/4*3/7+4/9*1/4+1/4*0/8+1/4*2/9)
on solving it gives a result of 28/69. - 9 years agoHelpfull: Yes(6) No(3)
- ..............IMPORTANT.............
PLZ DONT GET CONFUSED WITH BAYES THEOREM
here bayes theorem is not applicable....
https://www.youtube.com/watch?v=N0l5NuysZII here u can get the reason why??
the correct ans is 1/4*4/9=1/9.
- 8 years agoHelpfull: Yes(4) No(0)
- 1/3
Bcz only 3 basket have apple - 9 years agoHelpfull: Yes(2) No(4)
- Ankit Kumar Roy and Tejaswi VVDL have given the answer as 28/69 from basket number 2 and as 23/84 for selecting an apple from any one of the four baskets. How come probability of selecting an apple from basket number 2 is more than selecting an apple from any one of the baskets. It should be less. I agree with the answers of Syam Kumar
- 8 years agoHelpfull: Yes(1) No(1)
- this clear show . item taken then it ask from which bag . so its bays theorem ......go with ankit kumar's ans
- 6 years agoHelpfull: Yes(1) No(0)
- since an apple is already selected then we have to calculate the probability of it's belongingness to 2nd basket.
ans is 4/9.
- 9 years agoHelpfull: Yes(0) No(5)
- 4/9 as 4c1/9c1
- 9 years agoHelpfull: Yes(0) No(5)
- P(C3/H)= P(C3) P(H/C3) / (P(H) -> 1/3 * 1/2 / (1/3*1+1/3*0+1/3*1/2) ->1/3
- 6 years agoHelpfull: Yes(0) No(0)
- 45/69
total by apples - 6 years agoHelpfull: Yes(0) No(0)
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