Answer:
120
Explanation:
20+40+60 = 120
If we double it, we have to keep adding 20 each year and stop at 3 so the answer is 120
160
20 x 2 = 40
40 x 2 = 80
80 x 2 = 160
It stops at 3 years.
5.7m questions
7.4m answers