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Probability - A and B are two weak students....
A and b are two weak students in Mathematics. The chances of their solving a problem correctly is 1/8 and 1/12. The probability of them making a common mistake is 1/1001 and they obtain the same answer. Find the chance that their answer is correct.
Let E1 be the event that A and B solve correctly
E2 be the event that A and B solve incorrectly.
K be the event that they obtain same answer.
P(E1) = 1/8 x 1/12
P(K/E1)= 1000/1001
P(E2) = 7/8 x 11/12
P(K/E2) = 1/1001
Now by Baye's theorem,
P(E1/K) = P(E1)xP(K/E1)/.........
I got the answer as 1000/1077
The answer given is
There is a very very small difference in two answers.They are correct upto 3 decimal places.
Please tell me where is my mistake.
Homework Statement
A and b are two weak students in Mathematics. The chances of their solving a problem correctly is 1/8 and 1/12. The probability of them making a common mistake is 1/1001 and they obtain the same answer. Find the chance that their answer is correct.
The Attempt at a Solution
Let E1 be the event that A and B solve correctly
E2 be the event that A and B solve incorrectly.
K be the event that they obtain same answer.
P(E1) = 1/8 x 1/12
P(K/E1)= 1000/1001
P(E2) = 7/8 x 11/12
P(K/E2) = 1/1001
Now by Baye's theorem,
P(E1/K) = P(E1)xP(K/E1)/.........
I got the answer as 1000/1077
The answer given is
13/14
There is a very very small difference in two answers.They are correct upto 3 decimal places.
Please tell me where is my mistake.