Subtract 21/12 from 18/28
1st number: 18/28, 2nd number: 1 9/12
18/28 - 21/12 is -31/28.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 12 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 28 × 3 = 84,
18/28 = 18 × 3/28 × 3 = 54/84 - Likewise, for the 2nd fraction, since 12 × 7 = 84,
21/12 = 21 × 7/12 × 7 = 147/84 - Subtract the two like fractions:
54/84 - 147/84 = 54 - 147/84 = -93/84 - After reducing the fraction, the answer is -31/28
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