Subtract 28/90 from 81/12
1st number: 6 9/12, 2nd number: 28/90
81/12 - 28/90 is 1159/180.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 90 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 12 × 15 = 180,
81/12 = 81 × 15/12 × 15 = 1215/180 - Likewise, for the 2nd fraction, since 90 × 2 = 180,
28/90 = 28 × 2/90 × 2 = 56/180 - Subtract the two like fractions:
1215/180 - 56/180 = 1215 - 56/180 = 1159/180 - In mixed form: 679/180
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