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$800 Calculation

A Jeopardy show posed this question for $800: "75% of 200 + 200% of 75." The appropriate response is "What is 300?" but that is not my interest here.

Rather, how would you work that problem mentally?

Would you mentally say 75% of 200 is 3/4 of 200 or 150, then say 200% of 75 is twice 75 or 150, etc...?

Or, would you mentally say 75% of 100 is 75, so 75% of 200 is 150, while 100% of 75 is 75, so 200% of 75 is 150, etc.?

Or, would you rewrite (in your mind) that "75% of 200 + 200% of 75" is the same as "75% of 200 + 75% of 200 = 2 x [75% of 200] = 150% of 200 = 300"?

Or, would you....

Source: Jeopardy, Jan. 6, 2008