Question

$\frac{2}{5}$ of total number of students of a school come by car while $\frac{1}{4}$ of students come by bus to school. All the other students walk to school of which $\frac{1}{3}$ walk on their own and the rest are escorted by their parents. If 224 students come to school walking on their own, how many students study in that school?
[5 marks]

Answer 1

Let the number of students study in school be x.
Number of students come by car
$=\frac{2}{5}\times x=\frac{2}{5}x$

Number of students come by bus
$=\frac{1}{4}\times x=\frac{1}{4}x$
[1 mark]

Remaining students walk to school
$=x-(\frac{2}{5}x+\frac{1}{4}x)=x-\left(\frac{8x+5x}{20}\right)$
$=x-\frac{13x}{20}=\frac{20x-13x}{20}=\frac{7x}{20}$
[1 mark]

Now, number of students walk to school on their own
$=\frac{1}{3}$ of $\frac{7x}{20}=\frac{7x}{60}$
[1 mark]

Since, 224 students come to school on their own.

According to the question

$\Rightarrow \frac{7x}{60}=224\Rightarrow x=\frac{224\times 60}{7}\Rightarrow x=32\times 60=1920$

Hence, 1920 students study in that school.
[2 marks]