Subtract 81/12 from 7/90
1st number: 7/90, 2nd number: 6 9/12
7/90 - 81/12 is -1201/180.
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,
7/90 = 7 × 2/90 × 2 = 14/180 - Likewise, for the 2nd fraction, since 12 × 15 = 180,
81/12 = 81 × 15/12 × 15 = 1215/180 - Subtract the two like fractions:
14/180 - 1215/180 = 14 - 1215/180 = -1201/180
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