Question

Three coins are tossed together. The probability that at least one head comes up is

• A. \(\dfrac{3}{8}\)
• B. \(\dfrac{7}{8}\)
• C. \(\dfrac{1}{8}\)
• D. \(\dfrac{3}{4}\)

Hint:

To find the probability of "at least one", subtract the probability of "none" from 1.

Answer 1

The Correct Option is B

The total number of outcomes when three coins are tossed is: \[ 2^3 = 8 \] The only outcome where no head appears is TTT. So, only 1 outcome has zero heads. Hence, the number of favorable outcomes for "at least one head" = \(8 - 1 = 7\) So, required probability = \(\dfrac{7}{8}\)