Subtract 27/28 from 21/30
21/30 - 27/28 is -37/140.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 28 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 30 × 14 = 420,
21/30 = 21 × 14/30 × 14 = 294/420 - Likewise, for the 2nd fraction, since 28 × 15 = 420,
27/28 = 27 × 15/28 × 15 = 405/420 - Subtract the two like fractions:
294/420 - 405/420 = 294 - 405/420 = -111/420 - After reducing the fraction, the answer is -37/140
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