Subtract 21/8 from 12/84
1st number: 12/84, 2nd number: 2 5/8
12/84 - 21/8 is -139/56.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 8 is 168
Next, find the equivalent fraction of both fractional numbers with denominator 168 - For the 1st fraction, since 84 × 2 = 168,
12/84 = 12 × 2/84 × 2 = 24/168 - Likewise, for the 2nd fraction, since 8 × 21 = 168,
21/8 = 21 × 21/8 × 21 = 441/168 - Subtract the two like fractions:
24/168 - 441/168 = 24 - 441/168 = -417/168 - After reducing the fraction, the answer is -139/56
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