Subtract 81/70 from 12/84
1st number: 12/84, 2nd number: 1 11/70
12/84 - 81/70 is -71/70.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 70 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 84 × 5 = 420,
12/84 = 12 × 5/84 × 5 = 60/420 - Likewise, for the 2nd fraction, since 70 × 6 = 420,
81/70 = 81 × 6/70 × 6 = 486/420 - Subtract the two like fractions:
60/420 - 486/420 = 60 - 486/420 = -426/420 - After reducing the fraction, the answer is -71/70
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