The task is to generate the correct answer for a given math problem.
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Question: Problem: what decimal fraction is 90 ml of a litre ?

Answer: . 09


Question: Problem: a man rows his boat 110 km downstream and 90 km upstream , taking 3 hours each time . find the speed of the stream ?

Answer: 3.5


Question: Problem: ( 212 + 222 + 232 + . . . + 302 ) = ?

Answer:
2570