# A bag contains 3 red balls and 5 black balls. A ball is drawn at random from the bag. What is the probability that the ball drawn is (i) red ? (ii) not red?

**Solution:**

We will use the basic concepts of probability to solve the problem.

This question can be solved by using two steps.

Step (i): First find out the probability of drawing a red ball by using the formula given below.

Probability of an event = Number of possible outcomes/total number of favourable outcomes

Step (ii): After that, by using the formula for the sum of complementary event, find the probability of not getting a red ball.

P (E) + P (not E) = 1

(i) Number of red balls in a bag = 3

Number of black balls in a bag = 5

Total number of balls = 3 + 5 = 8

Probability of drawing red ball P(E) = Number of possible outcomes/Total number of favourable outcomes

Probability of drawing red ball = 3/8

(ii) Probability of not getting red ball P(not E) = 1 - P (E) = 1 - 3/8 = 5/8

**☛ Check: **NCERT Solutions for Class 10 Maths Chapter 15

**Video Solution:**

## A bag contains 3 red balls and 5 black balls. A ball is drawn at random from the bag. What is the probability that the ball drawn is (i) red ? (ii) not red?

NCERT Solutions for Class 10 Maths Chapter 15 Exercise 15.1 Question 8

**Summary:**

If a bag contains 3 red balls and 5 black balls, and a ball is drawn at random from the bag, then the probability that the ball drawn is red is 3/8 and the probability that the ball drawn is not red is 5/8.

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