Jan is 10 years old.
Kate is 30 years old.
Step-by-step explanation:
To solve this problem, we need to find a system of equations.
Now: Kate is three times as old as Jan.
This statement can be expressed as , beacuse "three times" indicates a product.
6 years ago: She was six times as old as he was.
This statement can be expressed as , notice that we had to subtract 6 units, representing 6 years in the past.
Let's replace the first equation into the second one
Therefore, Jan is 10 years old.
Then,
Therefore, Kate is 30 years old.