Subtract 21/7 from 28/12
1st number: 2 4/12, 2nd number: 3 0/7
28/12 - 21/7 is -2/3.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 7 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 12 × 7 = 84,
28/12 = 28 × 7/12 × 7 = 196/84 - Likewise, for the 2nd fraction, since 7 × 12 = 84,
21/7 = 21 × 12/7 × 12 = 252/84 - Subtract the two like fractions:
196/84 - 252/84 = 196 - 252/84 = -56/84 - After reducing the fraction, the answer is -2/3
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