Q2. - Algebra 2

Question

On a college math test, 18 students earned an A. This number is exactly $30\%$ of the total number of students in the class. State how many students are in the class.

 

A. $5$                                  B. 23

 

C. $48$                               D. 60

Step-by-Step Solution

Answer

Number of students in the class is 60 and the correct option is D.

Step 1 - State the definition of a variable.

A variable is a term that is used to represent an unknown value.

Here, let x be the number of students in the class.

Step 2 - Evaluate the value of x .

It is know that, 18 students got an A and these 18 students are $30\%$ of total number of students.

Since x is the total number of students in the class.

Then, $30\%$ of x is 18. That is,

 $\frac{30}{100}\times x=18$

Simplify the equation using multiplication and division,

 $\begin{array}{c}\frac{30}{100}\times x\times 100=18\times 100\\ 30x=1800\\ \frac{30x}{30}=\frac{1800}{30}\\ x=60\end{array}$

Hence, the value of x is 60 that is number of students in the class is 60.

Step 3 - State the conclusion.

The number of students in the class is 60. Therefore, option D is correct.