MCQ
A problem of mathematics is given to three students whose chances of solving the problem are $\frac{{1}}{{3}} , \frac{{1}}{{4}}$ and $\frac{{1}}{{5}}$ respectively. The probability that the question will be solved is
  • A
    $\frac{2}{3}$
  • B
    $\frac{3}{4}$
  • C
    $\frac{4}{5}$
  • $\frac{3}{5}$

Answer

Correct option: D.
$\frac{3}{5}$
d
(d) The probability of students not solving the problem are $1 - \frac{1}{3} = \frac{2}{3},$ $1 - \frac{1}{4} = \frac{3}{4}$ and $1 - \frac{1}{5} = \frac{4}{5}$

Therefore the probability that the problem is not solved by any one of them $ = \frac{2}{3} \times \frac{3}{4} \times \frac{4}{5} = \frac{2}{5}$

Hence the probability that problem is solved$ = 1 - \frac{2}{5} = \frac{3}{5}$.

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