Subtract 20/63 from 21/28
21/28 - 20/63 is 109/252.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 63 is 252
Next, find the equivalent fraction of both fractional numbers with denominator 252 - For the 1st fraction, since 28 × 9 = 252,
21/28 = 21 × 9/28 × 9 = 189/252 - Likewise, for the 2nd fraction, since 63 × 4 = 252,
20/63 = 20 × 4/63 × 4 = 80/252 - Subtract the two like fractions:
189/252 - 80/252 = 189 - 80/252 = 109/252
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