Answer:
170
Explanation:
each little mark is adding 20 to the 100 you see there and because the arrow is pointing somewhere in between two of the marks, it means it's just adding 10. Now you have to add 100 + the marks + 10
* remember you have three marks and each one of them is equal to 20 so when you add them, you get 60.
100 + 60 + 10 = 170