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A box contains 10 sample watches, 2 of w...

A box contains 10 sample watches, 2 of which are defective. If 2 are selected at random, the probability that both selected are defective is,

A

`(2)/(25)`

B

`(9)/(20)`

C

`(1)/(25)`

D

`(1)/(45)`

Text Solution

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The correct Answer is:
D
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Knowledge Check

  • A lot consists of 12 good pencils, 6 with minor defects and 2 with major defects. A pencil is choose at random. The probability that this pencil is not defective is

    A
    `3/5`
    B
    `3/(10)`
    C
    `4/5`
    D
    `1/2`

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