Subtract 56/15 from 54/21
1st number: 2 12/21, 2nd number: 3 11/15
54/21 - 56/15 is -122/105.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 15 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 21 × 5 = 105,
54/21 = 54 × 5/21 × 5 = 270/105 - Likewise, for the 2nd fraction, since 15 × 7 = 105,
56/15 = 56 × 7/15 × 7 = 392/105 - Subtract the two like fractions:
270/105 - 392/105 = 270 - 392/105 = -122/105
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