Question

A bag contains 12 red, 9 green, 8 blue and 5 yellow balls. A ball is drawn from the bag at random. Find the probability of getting:
(a) A green ball.
(b) A yellow ball.
(c) A white ball.

Answer 1

Hint: To get the required probability divide the number of favourable outcomes by the total number of outcomes. Total number of outcomes is the total number of balls we have. Find out the number of favourable outcomes according to the given conditions.

Complete step-by-step answer:
Probability means possibility. Probability is a measure of the likelihood of an event to occur. The probability formula is defined as the possibility of an event to happen is equal to the ratio of the number of favourable outcomes and the total number of outcomes.
It is given in the question that, there are 12 red balls, 9 green balls, 8 blue balls and 5 yellow balls in a bag.
So the total number of balls will be our total numbers of outcomes.
Total number of balls we have:
$\left( 12+9+8+5 \right)=34$
So if a ball is drawn from the bag at random we can get at most 34 different balls.
Therefore, our total number of outcomes will be 34.
Now, to find out the probability of getting a green ball we need the total number of favourable cases.
We have 9 green balls in total. So the total number of favourable cases will be 9.
So, the probability of getting a green ball is$\dfrac{9}{34}$ .
Similarly, we have 5 yellow balls in total. So the total number of favourable cases will be 5.
So, the probability of getting a yellow ball is $\dfrac{5}{34}$
There is no white ball in the bag. So we can’t draw a white ball from the bag. The favourable number of cases will be 0.
Therefore, the probability of getting a white ball is 0.

Note: We generally make mistakes while counting the total number of favourable cases. Favourable cases are or favourable outcomes are different from total number of possible outcomes. An outcome is a possible result of some event occurring. Favourable outcomes are the specific outcomes you are looking for.