Question

A box contains 18 balls out of which 'x'
are blue and others are red in colour.
The number of red balls is half the
number of blue balls.
what is the probability that a
ball drawn at random is a blue ball? what is the probability that a ball drawn
at random is a red balls ?​

Answer 1

Answer:. *P*(of getting blue ball) = 9/18 = 1/2

P(getting red ball) = 9/18 = 1/2

Answer 2

P(Getting a red balls) = $\dfrac{12}{36}$

Step-by-step explanation:

Given,

The total number of balls = 18

The number of red balls = x

∴ The number of blue balls = $\dfrac{x}{2}$

To find, the probabilityt of a ball drawn  at random is a red balls = ?

∴ x + $\dfrac{x}{2}$ = 18

⇒ $\dfrac{3x}{2}$ = 18

⇒ 3x = 18 × 2 = 36

⇒ x = $\dfrac{36}{3}$ = 12

∴ The number of red balls = 12

∴ P(Getting a red balls) = $\dfrac{12}{36}$

= $\dfrac{1}{3}$

Thus, P(Getting a red balls) = $\dfrac{12}{36}$