Question 726848
Let x = Kerri's age right now


In 10 years, she will be x+10 years old.


10 years ago, she was x-10 years old


So...


"In 10 years, Kerri's age will be 3 times what it was 10 years ago"


translates to


x+10 = 3(x-10)


solve for x


x+10=3(x-10)


x+10=3x-30


x=3x-30-10


x-3x=-30-10


-2x=-30-10


-2x=-40


x=(-40)/(-2)


x=20


So Kerri is currently <font color="red">20 years old</font>.