Question

The number of candidates who appeared in an examination was $13000$ of which $45\%$ were boys and the remaining girls. If $30\%$ boys and $40\%$girls qualified the examination, Find the number of candidates who did not qualify.

Answer 1

STEP 1:- Find the number of boys and girls

The number of candidates who appeared in an examination$=$$13000$

No. of boys $=$$45\%$

No. of girls$=100\%-45\%$

$=55\%$

No. of boys $=$$45\%$ of $13000$

$$\begin{gathered} =\frac{45}{100}\times 13000 \\ =45\times 130 \\ =5850 \end{gathered}$$

No. of girls $=55\%$ of $13000$

$$\begin{gathered} =\frac{55}{100}\times 13000 \\ =55\times 130 \\ =7150 \end{gathered}$$

STEP 2:- Find the number of candidates who did not qualify

No. of boys who qualified the exam$=30\%$ of the boys

No. of boys who did not qualified the exam$=100\%-30\%$

$=70\%$ of the boys

$70\%$ of $5850$$=\frac{70}{100}\times 5850$

$$\begin{gathered} =70\times 58.50 \\ =4095 \end{gathered}$$

No. of girls who qualified the exam$=40\%$ of the girls

No. of girls who did not qualified the exam$=100\%-40\%$

$=60\%$ of the girls

$60\%$ of $7150$$=\frac{60}{100}\times 7150$

$=4290$

Number of candidates who did not qualify$=4290+4095$

$=8385$

Hence, the total number of candidates who did not qualify is $8385$.