Find the probability of 4 turning up at east once in two tosses of a fair die.

Options

A. `(8)/(36)`
B. `(9)/(36)`
C. `(10)/(36)`
D. `(11)/(36)`

Answer

D

Explanation

`p=(1)/(6), q=(1-(1)/(6)) =(5)/(6) " and " n=2`
`P(X=r)=.^(n)C_( r) .p^(r ) .q^((n-r)) =.^(2)C_(r ).((1)/(6))^(r ).((5)/(6))^((2-r))`
P[at least one 4] =[P(X=1 or X=2) =P(X=1) + P(X=2)`