My current age is 4 times what my sister's age was 20 years ago. i am now twice as old as i was 20 years ago. ten years ago, my sister's age was 1/2 of my current age. ten years ago, my age was 1.5 times my sister's age. what is my current age?

Current age is 40. I think the key is in the second sentence

Let y = your current age

Let s = sister's current age

:

Write an equation for each statement, simplify as much as possible:

"my current age is 4 times what my sisters age was 20 years ago."

y = 4 (s-20)

y = 4s - 80

" I am now twice as old as i was 20 years ago."

y = 2 (y-20)

y = 2y - 40

40 = 2y - y

y = 40 yr, your present age

Right here you know enough to solve this

40 = 4s - 80

40 + 80 = 4s

s = 120/4

s = 30 is the sisters age