Answer:
140 scoops
Step-by-step explanation:
Assuming Masha started with 200 scoops of ice cream, each ate 140 scoops.
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The difference in ratio units is 3-2 = 1.
The difference in ice cream scoops is 200 -180 = 20, so each ratio unit must stand for 20 scoops of ice cream. That is, Masha and Liz ended with 3·20 = 60 and 2·20 = 40 scoops of ice cream remaining, respectively.
In order to have these numbers remaining, each had to eat ...
200 -60 = 180 -40 = 140 scoops of ice cream
