Question

Three symmetrical dice are thrown. The probability of obtaining a sum of $5$ points is

• A. $\frac{1}{6}$
• B. $\frac{1}{36}$
• C. $\frac{1}{216}$
• D. $\frac{1}{54}$

Answer 1

The correct option is B $\frac{1}{36}$

The different cases in which a sum of $5$ points can be obtained $=(1,1,3),(1,3,1),(3,1,1),(1,2,2),(2,1,2),(2,2,1)$
Number of cases$=5$
Total number of cases $=6\times 6\times 6=216$
The probability of obtaining a sum of $5$ points $=\frac{6}{216}=\frac{1}{36}$