JEE Main & Advanced Mathematics Probability Question Bank Self Evaluation Test - Probability-I

  • question_answer
    A box contains 10 identical electronic components of which 4 are defective. If 3 components are selected at random form the box, in succession, without replacing the units already drawn, what is the probability that two of the selected components are defective?

    A) 1/5

    B) 5/24

    C) 3/10

    D) 1/40

    Correct Answer: C

    Solution :

    [c] Total number of selecting 3 components out of \[10{{=}^{10}}{{C}_{3}}.\] Out of 3 selected components two defective pieces can be selected in \[^{4}{{C}_{2}}\] ways and one non-defective piece will be selected in \[^{6}{{C}_{1}}\]ways. Hence, required probability \[=\frac{^{6}{{C}_{1}}{{\times }^{4}}{{C}_{2}}}{^{10}{{C}_{3}}}=\frac{6\times 6\times 6}{10\times 9\times 8}=\frac{3}{10}\]


You need to login to perform this action.
You will be redirected in 3 sec spinner