Thursday, November 17, 2011

Question #8

8. How could you mentally find 40% of 180?

- 1) break 180 down to a friendly number. 180 = 100+80
- 2) Divide the % number to 100. 40% Divided by 100 = 0.4
- 3) Then multiply 0.4 to the friendly number 0.4 x 100 = 40
- 4) Divide the rest of the number 180 to 100. 80 Divided by 100 = 0.8
- 5) Multiply the answer to 40. 0.8 x 40 = 32
- 6) Then add 32 to 40. 32 + 40 = 72


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