What is the probability that a two digit number is not a prime number when a number is chosen at random?
A. $$\frac{7}{{30}}$$
B. $$\frac{{23}}{{30}}$$
C. $$\frac{{21}}{{90}}$$
D. $$\frac{{67}}{{90}}$$
Answer: Option B
Solution (By Examveda Team)
Two digit number = 10 . . . . . 99 = 90 numberPrime number between 1 to 100 = 25
Prime number between 1 to 10 = 2, 3, 5, 7 = 4
Prime number between 1 to 99 = 25 - 4 = 21
$${\text{Probability}} = \frac{{90 - 21}}{{90}} = \frac{{69}}{{90}} = \frac{{23}}{{30}}$$
This Question Belongs to Arithmetic Ability >> Probability
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