Question

What is the chance of throwing an ace in the first only of two successive throws with an ordinary die?

Answer 1

Chance of throwing ace in the first throw $=\frac{1}{6}$

Chance of throwing ace in second throw $=\frac{1}{6}$

Chance of not throwing ace in second throw $=1-\frac{1}{6}=\frac{5}{6}$

$\therefore$ required probability $=\frac{1}{6}\times \frac{5}{6}=\frac{5}{36}$