Question

The odds against student X solving a statistics problem are 8:6 and odds in favour of student y solving the same problem are 14:16. Find is the chance that neither of them solves the problem

Answer 1

The odds against X solving a problem are 8:6.

Let P(X') = P(X does not solve the problem)

= `8/(8 + 6)`

= `8/14`

So, the probability that X solves the problem

= P(X)

= 1 – P(X')

= `1 - 8/14`

= `6/14`

Similarly, let P(Y) = P(Y solves the problem) Since odds in favour of Y solving the problem are 14:16,

P(Y) = `14/(14 + 16)`

= `14/30`

So, the probability that Y does not solve the problem

= P(Y')

= 1 – P(Y)

= `1 - 14/30`

= `16/30`

Required probability = P(X' ∩ Y')

Since X and Y are independent events, X' and Y' are also independent events.

∴ Required probability = P(X').P(Y')

= `8/14 xx 16/30`

= `32/105`