Question

In a single throw of two dice, the probability of obtaining a total of $7$ or $9,$ is:

• A. $\frac{4}{9}$
• B. $\frac{1}{3}$
• C. $\frac{7}{18}$
• D. None of these

Answer 1

The correct option is D None of these

Let the outcomes of two dice be $x,y$.

For the sum to be $7$ , $x+y=7$. There are $6$ possibilities.

For the sum to be $9$ , $x+y=9$. There are $4$ possibilities.

Total number of possibilities for $7$ or $9$ is $10$.

The probability of obtaining total $7$ or $9$ is $\frac{10}{36}=\frac{5}{18}$.

Therefore option $D$ is correct.