Question:

Three dice are rolled. If $P(\text{all different})=\dfrac{p}{q}$ (coprime), then $q-p$ is equal to

Step-by-Step Solution

Key Concept: Favourable: $6\times5\times4=120$. Total: $6^3=216$. $P=\frac{120}{216}=\frac{5}{9}$.

$q-p=4$.

Correct Answer: 4