In four schools {B₁},{B₂},{B₃},{B₄} percentage of girls students is 12, 20, 13, 17 respectiv

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14.Probability

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In four schools ${B_1},{B_2},{B_3},{B_4}$ the percentage of girls students is $12, 20, 13, 17$ respectively. From a school selected at random, one student is picked up at random and it is found that the student is a girl. The probability that the school selected is ${B_2},$ is

A

$\frac{6}{{31}}$

B

$\frac{{10}}{{31}}$

C

$\frac{{13}}{{62}}$

D

$\frac{{17}}{{62}}$

Solution

(b)Favorable number of cases $= ^{20}{C_1} = 20$

Sample space $= ^{62}{C_1} = 62$

$\therefore $ Required probability $= \frac{{20}}{{62}} = \frac{{10}}{{31}}$.

Standard 11

Mathematics

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