Question

Question 18 (ii)
A box contains 90 discs which are numbered from 1 to 90. If one disc is drawn at random from the box, find the probability that it bears a perfect square number.

Answer 1

Total number of outcomes = 90
From 1 to 90, the perfect squares are 1, 4, 9, 16, 25, 36, 49, 64 and 81.
$\therefore$ Favourable outcomes = 9
Hence, P (getting a perfect square number) = $\frac{9}{90}=\frac{1}{10}$