Step 1: Understand the question and verify that the given events are complementary events or not.

GIVEN: The probability of 2 students not having the same birthday = 0.992

Event 1: The probability of 2 students not having the same birthday P(E)

Event 2: The probability of 2 students having the same birthday P(\bar{E})

These two events are complement to each other

Step 2: Calculate the probability of 2 students having the same birthday

We know that;

Sum of complementary events = 1

P(E) + P(\bar{E}) = 1

P(\bar{E}) = 1 - P(E)

P(\bar{E}) = 1 - 0.992

P(\bar{E}) = 0.008

Therefore; the probability of 2 students having the same birthday = 0.008