Question

There are 30 students in a class. Twenty percent got an A on the last test. How many students got an A?

Answer 1

Hint:In order to express a mathematical problem explained in words we have to take all the relevant and important information mentioned in the word problem and represent it in a much easier way like an equation. After representing it in the symbolic form we have performed the basic arithmetic operations as specified in the question. Eventually we would be able to solve the question. So by using the above definition and techniques we can solve the given question.

Complete step by step solution:
Given statements:
$
{\text{Total number of students: }}30...........................\left( i \right) \\
{\text{Students who got an A: }}20\;{\text{percent}}...................\left( {ii} \right) \\
$
Now we need to find the total number of students who got an A.
For that we have to express the given students mathematically and then solve it.
We also know that $20{\text{ percent = }}\dfrac{{20}}{{100}}....................\left( {iii} \right)$
Now we can observe and say from the given statements that the number of students who got an A can be expressed as:
\[
{\text{number of students who got an A = }}20\,{\text{percent of total}} \\
{\text{ = }}20\,{\text{percent of }}30......................\left( {iv} \right) \\
\]
Now we can write (iii) on comparing with (ii) as:
\[{\text{number of students who got an A = }}\dfrac{{20}}{{100}} \times 30..............\left( v \right)\]
Now on solving (iv) we can find the number of students who got an A.
\[
{\text{number of students who got an A = }}\dfrac{{20}}{{100}} \times 30 \\
= 2 \times 3 \\
= 6 \\
\]
Therefore the total number of students who have got an A would be: 6.

Note: On solving similar word problems, it’s advisable to adopt the above prescribed method since it’s easy to understand and execute. Also while solving word problems it’s important to read the question properly. After reading the question properly one has to separate the relevant and irrelevant information carefully.