Question

Three coins are tossed simultaneously. X is the number of heads. Then the expected value of X is ______.

Options

• 1

• 1.5

• 1.9

• 1.017

Answer 1

Three coins are tossed simultaneously. X is the number of heads. Then the expected value of X is 1.5.

Explanation:

When three fair coins are tossed, each coin has a 0.5 probability of showing heads.

The expected number of heads is E(X) = 3 × 0.5 = 1.5.