Question

If a dice is thrown twice, then the probability of getting $1$ in the first throw only is

• A. $\frac{1}{36}$
• B. $\frac{3}{36}$
• C. $\frac{5}{36}$
• D. $\frac{1}{6}$

Answer 1

The correct option is C

$\frac{5}{36}$

Explanation for the correct option:

Find the required probability:

Probability of obtaining $1$ in the first throw, $P\left(X\right)=\frac{1}{6}$

Probability of not obtaining $1$ in the second throw, $P\left(Y\right)=\frac{5}{6}$

$\because$$X$ and $Y$ are independent events

$\therefore$the required probability is, $\begin{array}{rcl}P\left(X\right)P\left(Y\right)& =& \left(\frac{1}{6}\right)\left(\frac{5}{6}\right)\end{array}$

$\begin{array}{rcl}& =& \frac{\mathbf{5}}{\mathbf{36}}\end{array}$

Hence, Option ‘C’ is Correct.