A lot consists of 12 good pencils, 6 with minor defects and 2 with major defects. A pencil is choose

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14.Probability

easy

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

A

$\frac{3}{5}$

B

$\frac{3}{{10}}$

C

$\frac{4}{5}$

D

$\frac{1}{2}$

Solution

(a) Required probability $ = \frac{{{}^{12}{C_1}}}{{{}^{20}{C_1}}} = \frac{3}{5}.$

Standard 11

Mathematics

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