Total number of balls = 24
Number of red balls = x
Number of whit balls = 2x
Number of bule balls = 3x
Total balls = 24
∴ 1x+2x+3x=24
⇒ 6x=24
⇒ x=4
So, Number of red balls = x =1×4=4
Number of white balls =2x=2×4=8
Number of white balls =3x=3×4=12
(i) Randomly selected ball is not red
∴ Number of favourable outcomes for the ball is not red = 24-4= 20
∴ F(E)=20andT(E)=24
∴ P(not red)=
F(E)
T(E)
=
20
24
=
5
6
∴ P(E)=
5
6
is the required probability.
(iii) Number of favourable outcomes for the event that the selected ball is white, F(E) = 8
∴ P (balls is white) =
8
24
=
1
3
∴ P(E)=
1
3
is the required probability.
