Evaluate without using a calculator. Then, check your answers with a calculator.
15% of 40
320% of 600
17.5% of 20
2041% of 50
The total rain precipitation of last summer was 350 mm. If it increased by 1221% this summer, what was the rain precipitation this summer?
0%
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In this section, we will try to estimate the percent of a number without using a calculator. The trick is to breakdown the percent into smaller percent first. These smaller percentages are easier for mental calculation.
