Subtract 21/18 from 12/28
1st number: 12/28, 2nd number: 1 3/18
12/28 - 21/18 is -31/42.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 18 is 252
Next, find the equivalent fraction of both fractional numbers with denominator 252 - For the 1st fraction, since 28 × 9 = 252,
12/28 = 12 × 9/28 × 9 = 108/252 - Likewise, for the 2nd fraction, since 18 × 14 = 252,
21/18 = 21 × 14/18 × 14 = 294/252 - Subtract the two like fractions:
108/252 - 294/252 = 108 - 294/252 = -186/252 - After reducing the fraction, the answer is -31/42
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