If A and B each toss three coins. The probability that both get the same number of heads is

The probability that A gets r heads in three tosses of a coin isP(X=r)=3Cr12r123−r=3Cr123The probability that A and B both get r heads in three tosses of a coin is 3Cr1233Cr123= 3Cr2126Hence, the required probability is ∑r=03  3Cr2126=126{1+9+9+1}=2064=516