Question

A bag contains 4 red, 5 black and 6 white balls. A ball is drawn from the bag at random. Find the probability that the ball drawn is :
(a)white
(b)red
(c)not black
(d)red or white

Answer 1

SOLUTION :  

GIVEN : Number of red balls = 4

Number of white balls = 6

Number of black balls = 5

Total number of balls in a bag = 4 + 6 + 5 = 15

Total number of outcomes = 15

(i) Let E1 = Event  of selecting that a  ball drawn is white

Number of white balls = 6

Number of outcome favourable to E = 6

Probability (E1) = Number of favourable outcomes / Total number of outcomes

P(E1) = 6/15 = 2/5

Hence, the required probability of getting a white ball , P(E1) = 2/5 .

(ii) Let E2 = Event  of selecting that a ball drawn is red

Number of outcome favourable to E = 4  

Probability (E2) = Number of favourable outcomes / Total number of outcomes

P(E2) = 4/15

Hence, the required probability of getting a red ball , P(E2) = 4/15 .

(iii) Let E3 = Event  of selecting that a  ball drawn is not black

Number of balls that are not black = (6 + 4) = 10

Number of outcome favourable to E3 = 10

Probability (E3) = Number of favourable outcomes / Total number of outcomes

P(E3) = 10/15 = 2/3

Hence, the required probability of getting a a  ball drawn is not black, P(E3) = 2/3 .

(iv) Let E4 = Event  of selecting that a ball drawn is red or white

Number of balls that are drawn is red or white= (4+6) = 10

Number of outcome favourable to E = 10

Probability (E4) = Number of favourable outcomes / Total number of outcomes

P(E4) = 10/15 = 2/3

Hence, the required probability of getting a red or white ball , P(E4) = ⅔ .

HOPE THIS ANSWER WILL HELP  YOU….

Answer 2

Solution :-

A number of red balls in bag = 4

Number of black balls in a bag = 5

Number of White balls in a bag = 6

Total number of balls in a bag =

4 + 5 + 6 = 15

Total number of favourable outcomes = 15

(I) Probability that the ball drawn is white is

= > 6/15 = 2/5

(ii) Probability of getting a red ball
= > 4/15

(iii) Probability of not getting a red ball is
=> 5+6/15 = 11/15

(IV) Prbability of getting a red or a white ball

= > 4/15 + 6/15

= > 10/15 = 2/3

==============
@GauravSaxena01