Subtract 81/12 from 28/90
1st number: 28/90, 2nd number: 6 9/12
28/90 - 81/12 is -1159/180.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 12 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 90 × 2 = 180,
28/90 = 28 × 2/90 × 2 = 56/180 - Likewise, for the 2nd fraction, since 12 × 15 = 180,
81/12 = 81 × 15/12 × 15 = 1215/180 - Subtract the two like fractions:
56/180 - 1215/180 = 56 - 1215/180 = -1159/180
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