Question

the sum of the two numbers is 30. the first number is twice as large as the second one, what are the numbers?

Answer 1

Let f = first number and s = second number.

f + s = 30

f = 2s

2s + s = 30

3s = 30, so s = 10 and f = 20.

The first number is 20, and the second number is 10.