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.

☛ Related Questions:

• A box contains 5 red marbles, 8 white marbles and 4 green marbles. One marble is taken out of the box at random. What is the probability that the marble taken out will be(i) red ?(ii) white ?(iii) not green?
• A piggy bank contains hundred 50p coins, fifty ₹ 1 coins, twenty ₹ 2 coins and ten ₹ 5 coins. If it is equally likely that one of the coins will fall out when the bank is turned upside down, what is the probability that the coin (i) will be a 50 p coin ? (ii) will not be a ₹ 5 coin?
• Gopi buys a fish from a shop for his aquarium. The shopkeeper takes out one fish at random from a tank containing 5 male fish and 8 female fish (see Fig. 15.4). What is the probability that the fish taken out is a male fish?
• A game of chance consists of spinning an arrow which comes to rest pointing at one of the numbers 1, 2, 3, 4, 5, 6, 7, 8 (see Fig. 15.5 ), and these are equally likely outcomes. What is the probability that it will point at(i) 8 ?(ii) an odd number?(iii) a number greater than 2?(iv) a number less than 9?