Question

The sum of two numbers is 30. One number is twice as large as the second number.

Answer 1

One number can be represented as x and the other number can be represented as 2x since it's twice as large as the other. In an equation it's 2x + x = 30 which is 3x = 30 then solve for x and you get your value as 10

Answer 2

let a+b=30
a=2b
2b+b=30
b=10
a=20