Two cards are drawn successively with replacement from a well-shuffled pack of 52 cards. Then mean of number of tens is

Step-by-step solution

Probability of getting ten = 4 52 = 1 13 Probability of getting a card without ten = 12 13 Let random variable X denotes the number of tens. Possible values of X are 0,1,2 Consider following probability distribution table. array |l|c|c|c| X =x & 0 & 1 & 2 P ( X =x) & 12 13 12 13 & 1 13 12 13 + 12 13 1 13 & 1 13 1 13 array Required mean aligned & =0+1 ( 12 13 13 + 12 13 13 )+2 ( 1 13 1 13 ) & = 24 169 + 2 169 & = 26 169 & = 2 13 aligned