Subtract 28/21 from 12/28
1st number: 12/28, 2nd number: 1 7/21
12/28 - 28/21 is -19/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 21 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 28 × 3 = 84,
12/28 = 12 × 3/28 × 3 = 36/84 - Likewise, for the 2nd fraction, since 21 × 4 = 84,
28/21 = 28 × 4/21 × 4 = 112/84 - Subtract the two like fractions:
36/84 - 112/84 = 36 - 112/84 = -76/84 - After reducing the fraction, the answer is -19/21
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