Subtract 27/70 from 20/21
20/21 - 27/70 is 17/30.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 70 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 21 × 10 = 210,
20/21 = 20 × 10/21 × 10 = 200/210 - Likewise, for the 2nd fraction, since 70 × 3 = 210,
27/70 = 27 × 3/70 × 3 = 81/210 - Subtract the two like fractions:
200/210 - 81/210 = 200 - 81/210 = 119/210 - After reducing the fraction, the answer is 17/30
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