Question

Suppose 60% of the graduating class in a certain high school goes to college. If 240 students from this graduating class are going to college, how many students are in the class?

Answer 1

Given :-

Percentage of the total number of students from a graduating class who go to college=60%

Number of students from a graduating class that go to college =240

Which means :-

Let the total number of students in the graduating class be x.

$= 60 \: \% \: \: of \: \: \: x = 240$

$= \frac{60}{100} \times x = 240$

$= \frac{60x}{100} = 240$

$=60x = 240 \times 100$

$= 60x = 24000$

$= x = \frac{24000}{60}$

$= x = \frac{24000 \div 60}{60 \div 60}$

$= x\bold{ = 400}$

Thus, the total number of students in the graduating class of a high school =400

The number of students who were in the class and didn't go to college:-

$= 400 - 240$

$=\bold{ 160}$

Thus, number of students who didn't go to college after the graduating class in high school=160

Now let us check whether or not we have found out the correct number of students who were in the class after the graduating class by checking if or not 240 and 40% of 400 adds up to form 400:-

$= 240 + 40\% \: \: \: of \: \: \: 400$

$= 240 + \frac{40}{100} \times 400$

$= 240 + \frac{16000}{100}$

$= 240 + 160$

$=\bold {400}$

As 240 and 40% of 400 adds up to form 400,we can conclude that we have found out the correct number of students in the class.

Therefore, the total number of students in the class were=400 out of which the number of students who are in the class =160