Subtract 81/56 from 21/70
1st number: 21/70, 2nd number: 1 25/56
21/70 - 81/56 is -321/280.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 56 is 280
Next, find the equivalent fraction of both fractional numbers with denominator 280 - For the 1st fraction, since 70 × 4 = 280,
21/70 = 21 × 4/70 × 4 = 84/280 - Likewise, for the 2nd fraction, since 56 × 5 = 280,
81/56 = 81 × 5/56 × 5 = 405/280 - Subtract the two like fractions:
84/280 - 405/280 = 84 - 405/280 = -321/280
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