Subtract 21/30 from 21/28
21/28 - 21/30 is 1/20.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 30 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 28 × 15 = 420,
21/28 = 21 × 15/28 × 15 = 315/420 - Likewise, for the 2nd fraction, since 30 × 14 = 420,
21/30 = 21 × 14/30 × 14 = 294/420 - Subtract the two like fractions:
315/420 - 294/420 = 315 - 294/420 = 21/420 - After reducing the fraction, the answer is 1/20
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