Q4 of 50 Page 1

In a family of 3 children, the probability of having at least one boy is

Given a family of 3 children. Let boy be denoted by ‘b’ and girl by ‘g’.


The number of possible outcomes are:


{g, g, g}, {g, g, b}, {g, b, g}, {b, g, g}, {b, b, g}, {b, g, b}, {g, b, b}, {b, b, b}


Let E be the event ‘having at least one boy’. The number of outcomes favourable to E are 7.


We know that probability of an event E, P (E)


⇒ P (≥ 1 boy)


The probability of having at least one boy is 7/8.

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