Question

The average of two numbers is 18. One of the numbers is twice the other. What is the larger number?

Answer 1

let the 1st number = x so the other number is 2x

then

(x + 2x)/2 = 18

or

(3x)/2= 18

solve for x

Answer 2

Ok, so we have two numbers: \(a, b\)
We know \(\Large \frac{a+b}{2} = 18\) and \(a = 2b\)

This is a system of equations. Do you know how to solve for them?