How do you estimate $4975 times 78$ by rounding?

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Answer 1 · 2016-12-04T20:10:36

$5,000*80=400,000$

Round 4,975 to 5,000 and 78 to 80. Now, you can mentally multiply 5,000 by 80 to get a product of 400,000.

How do you estimate 4975 times 784975 times 78 by rounding?