# Aclass has 18 girls. Girls make up 60% of the class. How many students are there in the class?

##### 1 Answer
Oct 19, 2016

$30$ students in the class.

#### Explanation:

There are several which in which we can approach this question:

We can do this question using direct proportion.

"If 18 girls represent 60%, how many students represent 100%?"

$\frac{18}{60} = \frac{x}{100}$

$x = \frac{18 \times 100}{60}$

$30$ students altogether.
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We can make and solve an equation.
Let the number of students be $x$

"60% of the students are 18 girls"

$\frac{60}{100} \times x = 18$

$x = 18 \times \frac{100}{60}$

$x = 30$ students
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We can increase the number of girls in the ratio $100 : 60$

$18 \times \frac{100}{60} = 30$ students

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In each case the calculation is the same, but there is a different approach and different reasoning.