Subject: General Aptitude · Chapter: Probability · Exam: · Marks: · Difficulty:
What is the probability of getting a sum 9 from two throws of a dice?
(a)$\frac{1}{6}$
(b)$\frac{1}{8}$
(c)$\frac{1}{9}$
(d)$\frac{1}{12}$
Answer
Answer (as printed): C
Explanation
In two throws of a die, $n(\mathrm{S})=(6 \times 6)=36$. Let $E=$ event of getting a sum 9 $=\{(3,6),(4,5),(5,4),(6,3)\}$. $$\therefore \quad P(E)=\frac{n(E)}{n(S)}=\frac{4}{36}=\frac{1}{9} .$$