## Question

Each of two persons *A* and *B* toss three fair coins. The probability that both get the same number of heads is

### Solution

5/16

Let *X* be the number of heads obtained by *A* and *Y* be the number of heads obtained by *B*. Note that both *X* and *Y* are binomial variate with parameters*n* = 3 and *P* = 1/2.

Probability that both A and B obtain the same number of heads is

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