A fair coin is tossed 5 times.What is the probability that exactly 2 heads are observed?
A)0.313
B)0.073
C)0.400
D)0.156
E)0.250

Question

Quizplus · Accepted Answer

There are a total of 2^5 = 32 possible outcomes when a fair coin is tossed 5 times. The number of ways to get exactly 2 heads in 5 tosses can be calculated using the binomial coefficient formula: 
C(5,2) = 5!/(2!3!) = 10
So, there are 10 ways to get exactly 2 heads. 
The probability of getting exactly 2 heads can be calculated as follows:
P(exactly 2 heads) = number of ways to get 2 heads / total number of possible outcomes = 10/32 = 0.313
Therefore, the best choice is A.

A Fair Coin Is Tossed 5 Times