It is given that in a group of 3 students, the probability of 2 students not having the same birthday is 0.992. What is the probability that the 2 students have the same birthday?

Solution:

We use the basic formula of probability to solve the problem.

We know that the sum of two complementary events is equal to 1.

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

By putting the given values in the above equation, we can find out the probability of not happening of the event.

The probability of 2 students not having the same birthday P(not E) = 0.992

Probability of 2 students having the same birthday P(E) = 1 - 0.992 = 0.008

Thus, the probability that 2 students have the same birthday is equal to 0.008.

☛ Check: NCERT Solutions Class 10 Maths Chapter 15

Video Solution:

It is given that in a group of 3 students, the probability of 2 students not having the same birthday is 0.992. What is the probability that the 2 students have the same birthday?

NCERT Solutions for Class 10 Maths Chapter 15 Exercise 15.1 Question 7

Summary:

If it is given that in a group of 3 students, the probability of 2 students not having the same birthday is 0.992, then the probability that the 2 students have the same birthday is 0.008.

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