Question

Question 27(iii)
A bag contains 10 red, 5 blue and 7 green balls. A ball is drawn at random. Find the probability of this ball being a not a blue ball.

Answer 1

If a ball is drawn out of 22 balls (5 blue + 7 green + 10 red), then the total number of outcomes are
n(S) = 22
Let $E_3$ = Event getting a red ball or a green ball i.e., not a blue ball.
$n\left(E_3\right)=(10+7)=17$
$\therefore$ Required probability $=\frac{n\left(E_3\right)}{n\left(S\right)}=\frac{17}{22}$