Answer:
in five years.
Step-by-step explanation:
I'm not good at explaining this but you can keep adding years to your equation until you get the answer to be 3. For example your starting equation is 85/25 which = 3.4 years, you can keep going like 86/26 = 3.3 years, 87/27 =3.2 years until you get to 3. When the terracotta bust is 90 years old and the marble bust is 30, it will be three times as old. (90/30 is simplified to 9/3 then to 3.)
