Kiko is now 6 times as old as his sister. In 6 years, he will be 3 times as old as his sister. What

Kiko is now 6 times as old as his sister. In 6 years, he will be 3 times as old as his sister. What is their present age?

Let k be Kiko's present age
Let s be Kiko's sisters age.

We're given two equations:

1. k = 6s
2. k + 6 = 3(s + 6)

To solve this system of equations, we substitute equation (1) into equation (2) for k:
6s + 6 = 3(s + 6)

Typing this equation into our math engine to solve for s, we get:
s = 4

To solve for k, we substitute s = 4 into equation (1) above:
k = 6 * 4
k = 24