A fair coin is tossed three times. What is the probability of getting exactly two heads?

easy 1 mark Class 12 · Mathematics · Probability

Answer

\frac{3}{8}

The correct answer is $\frac{3}{8}$ — Probability = favourable / total = $3/8$ .

Step-by-step solution

Identify the experiment: three independent tosses each with two outcomes.
The number of possible outcomes is $2^{3} = 8$ .
Count the favorable outcomes: exactly two heads can occur in $(2 3) = 3$ ways (HHT, HTH, THH).
Probability = favourable / total = $3/8$ .

Common mistake: Counting 6 favourable cases instead of 3 by treating order incorrectly.

Concept tested: Binomial probability for small n