Question

If the sum of two numbers is $640$ and their difference is $280$, then the numbers are

• A. $140,500$
• B. $180,460$
• C. $130,510$
• D. $150,490$

Answer 1

The correct option is B $180,460$

Let the numbers be x and y. Then
$x+y=640$ ......(1)
$\underset{–}{x-y=280}$ .........(2)
Equation (1) + equation (2):$2x=920$
$x=460$
Using in (1), we get $x+460=640$
$x=640-460=180$
Therefore, the numbers are 180 and 460.