Question

A box contains $30$ discs which are numbered $1$ to $30$. If one disc is drawn at random from the box, find the probability that it bears
(i) a two digit number
(ii) a perfect square number

Answer 1

Probability of an event is defined as the ratio of favorable outcomes to that of the total outcomes.

(i) Number of two-digit numbers in the range $1-30$ is $21$.

Hence, probability that the drawn disc is a two digit number is:

$P_1=\frac{21}{30}=0.7$

(ii) Number of perfect square numbers in the range $1-30$ is $5$.

Hence, probability that the drawn disc is a perfect square number is:

$P_2=\frac{5}{30}=0.167$