Question

Two fair coins are tossed. What is the probability that at least one coin lands a tail?

• A. $\frac{1}{5}$
• B. $\frac{3}{4}$
• C. $\frac{5}{6}$
• D. $\frac{2}{3}$

Answer 1

The correct option is B $\frac{3}{4}$

$P$ (Both coins land heads) $=$ $\frac{1}{2}\times \frac{1}{2}=\frac{1}{4}$

$P$(At least one coin lands tails) $=$ $1-\frac{1}{4}=\frac{3}{4}$