Subtract 80/21 from 45/56
1st number: 45/56, 2nd number: 3 17/21
45/56 - 80/21 is -505/168.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 56 and 21 is 168
Next, find the equivalent fraction of both fractional numbers with denominator 168 - For the 1st fraction, since 56 × 3 = 168,
45/56 = 45 × 3/56 × 3 = 135/168 - Likewise, for the 2nd fraction, since 21 × 8 = 168,
80/21 = 80 × 8/21 × 8 = 640/168 - Subtract the two like fractions:
135/168 - 640/168 = 135 - 640/168 = -505/168
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