Question

A $6$-sided die is rolled. What is the probability of rolling a number less than $8$?

Answer 1

Favorable outcomes obtained when we roll a die are $1,2,3,4,5$ and $6$.

All the outcomes obtained are less than $8$.

Let $\text{P(N<8)}$ denotes the probability of obtaining a number less than 8 on rolling the die.

$\text{P(N<8)}=\frac{\text{Number of favourable outcomes}}{\text{Total number of outcomes}}$

In this case,
Number of favourable outcomes $=6$
Total number of outcomes $=6$

$\text{P(N<8)}=\frac{6}{6}$

$\text{P(N<8)}=1$

We can say that rolling a number less than $8$ is a certain event because all the numbers on a die are less than $8$.

Hence, the probability of rolling a number less than $8$ is $1$.