Question

A six faced fair dice is thrown until $1$ comes, then the probability that $1$

• A. $5/11$
• B. $5/6$
• C. $6/11$
• D. $1/6$

Answer 1

The correct option is A $5/11$

The required probability
$=\frac{1}{6}.\frac{5}{6}+\frac{1}{6}.{\left(\frac{5}{6}\right)}^3+...=\frac{1}{6}.\frac{5}{6}[1+{\left(\frac{5}{6}\right)}^2+...]=\frac{5}{11}$