Subtract 21/63 from 20/28
20/28 - 21/63 is 8/21.
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,
20/28 = 20 × 9/28 × 9 = 180/252 - Likewise, for the 2nd fraction, since 63 × 4 = 252,
21/63 = 21 × 4/63 × 4 = 84/252 - Subtract the two like fractions:
180/252 - 84/252 = 180 - 84/252 = 96/252 - After reducing the fraction, the answer is 8/21
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