Subtract 81/70 from 27/28
1st number: 27/28, 2nd number: 1 11/70
27/28 - 81/70 is -27/140.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 70 is 140
Next, find the equivalent fraction of both fractional numbers with denominator 140 - For the 1st fraction, since 28 × 5 = 140,
27/28 = 27 × 5/28 × 5 = 135/140 - Likewise, for the 2nd fraction, since 70 × 2 = 140,
81/70 = 81 × 2/70 × 2 = 162/140 - Subtract the two like fractions:
135/140 - 162/140 = 135 - 162/140 = -27/140
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