A pair of dice is thrown. Find the probability of getting the sum 8 or more, if 4 appears on the first die.

Explanation

Let A= first die shows `4`

Let B shows the sum of the numbers on two dice is 8 or more.
`
A={(4,1),(4,2),(4,3),(4,4)(4,5),(4,6)}`
`
n(A)=6`
`
n(A)=6`
`
B={(2,6),(3,5),(3,6),(4,4),(4,5),(4,6),(5,3),(5,4),(5,5)(5,6),(6,2),(6,3),(6,4),(6,5),(6,6)}`
`
n(B)=15`

then ,
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