Question

If the difference of two numbers is 12 and one number is four times the other number, then their sum is:

• A. 14
• B. 16
• C. 18
• D. 20

Answer 1

The correct option is D 20

Let the first number be $x$
Then the other number $=4x$
Difference between them = 12
<!--td {border: 1px solid #ccc;}br {mso-data-placement:same-cell;}--> $\Rightarrow 4x-x=12$
<!--td {border: 1px solid #ccc;}br {mso-data-placement:same-cell;}--> $\Rightarrow 3x=12$
<!--td {border: 1px solid #ccc;}br {mso-data-placement:same-cell;}--> $\Rightarrow x=4$
∴ The numbers are 4 and 16.
∴ Their sum = 16 + 4 = 20