Subtract 21/30 from 12/28
12/28 - 21/30 is -19/70.
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,
12/28 = 12 × 15/28 × 15 = 180/420 - Likewise, for the 2nd fraction, since 30 × 14 = 420,
21/30 = 21 × 14/30 × 14 = 294/420 - Subtract the two like fractions:
180/420 - 294/420 = 180 - 294/420 = -114/420 - After reducing the fraction, the answer is -19/70
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