A problem in Mathematics is given to three students whose chances of solving it are $\frac{1}{2}, \frac{1}{3}, \frac{1}{4}$, respectively. If the events of solving the problem are independent, then the probability that the problem will be solved, is |
$\frac{1}{4}$ $\frac{1}{3}$ $\frac{1}{2}$ $\frac{3}{4}$ |
$\frac{3}{4}$ |
The correct answer is Option (4) → $\frac{3}{4}$ ## Let $A, B, C$ be the respective events of solving the problem. Then, $P(A) = \frac{1}{2}$ $P(B) = \frac{1}{3}$ and, $P(C) = \frac{1}{4}$ Here, $A, B, C$ are independent events. Problem is solved if at least one of them solves the problem. $\text{Required probability} = P(A \cup B \cup C)$ $= 1 - P(\bar{A})P(\bar{B})P(\bar{C})$ $= 1 - \left(1 - \frac{1}{2}\right)\left(1 - \frac{1}{3}\right)\left(1 - \frac{1}{4}\right)$ $= 1 - \frac{1}{4}$ $= \frac{3}{4}$ |