Brain Teasers & Mental Math
Mental math: what is 1/8 as a percentage, and 7/8?
Model answer
1/8 = 12.5%; 7/8 = 87.5%.
Anchor on the powers-of-two fractions: 1/2 = 50%, 1/4 = 25%, 1/8 = 12.5%, 1/16 = 6.25% — each halves the previous. Then 7/8 = 1…
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