Total no. of possible outcomes = 25 {1, 2, 3…. 25}
Let E = Event of getting a prime no.
So, the favourable outcomes are 2, 3, 5, 7, 11, 13, 17, 19, 23
No. of favourable outcomes = 9
Probability, P(E) = Number of favourable outcomes/ Total number of outcomes
P(E) = 9/25
The,
¯
E
= Event of not getting a prime
Therefore, the probability of selecting a number which is not prime is 16/25.
