Question

find the probability of number selected from the numbers 1 2 3.......10 is a prime number

Answer 1

No of favourable outcomes=3
{3,5,7}
Total no of events=10
P(E)=no of favourable outcomes/total number of outcomes
=3/10

Answer 2

THE TOTAL NO. OF SAMPLE SPACE IS  n{s}=10
      prime no. are n{e}=2,3,5,7 =4
p{e}=n{e}/n{s}
     =  4/10=2/5