Question

Two digit number is formed by the following digits 2 3 5 7 9 without repetition find the probability of following events .
event a number so form a perfect square.
event b number so form a prime number

Answer 1

event a be the number 9

event b be the number 2,3,5,7

Answer 2

S=(23 25 27 29 32 35 37 39 52 53 57 59 72 73 75 79 92 93 95 97 99)

A(25 ) n(A)=1

P(A) =1/25