Question

Below is a chart given for the number of

students from different departments in
Technical / engineering college for the year
2019. The proportion of male to female
students in each department is 5:4. There are
40 males in Electrical Engineering. What is
the difference between numbers of female
students in the Civil department and the
female students in the Mechanical
department?
*
Electrical
20%
Mechanical
Computer
science
20%
Civil
30%

Answer 1

32

Explanation:

From the chart

• Electrical 20%
• Mechanical 10%
• Computer science 20%
• Civil 30%

Male: Female=5:4

Number of Males in Electrical Engineering=40

Let the total population of the student=x

Therefore:

`\frac59 * 20\%$ of x=40`

5*0.2x=40*9

x=360

Number of Females in the Civil Department

`=\frac49 * 30\%$ of 360`

=48

Number of Females in the Mechanical Department

`=\frac49 * 10\%$ of 360`

=16

Difference in the number of females

=48-16

=32