If a dice is thrown twice, the probability of occurrence of 4 atleast once is

Options

A. `(11)/(36)`
B. `(35)/(36)`
C. `(7)/(12)`
D. None of these

Answer

A

Explanation

(a) Probability of getting 4, `p=(1)/(6)`
Probability of not getting 4, `q=1-(1)/(6)=(5)/(6)`
`:.` Probability of getting 4 atleast once in two throws of dice
`=""^(2)C_(1)((1)/(6))((5)/(6))+""^(2)C_(2)((1)/(6))^(2)=2.(5)/(36)+1.(1)/(36)=(11)/(36)`