Subtract 81/12 from 42/90
1st number: 42/90, 2nd number: 6 9/12
42/90 - 81/12 is -377/60.
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,
42/90 = 42 × 2/90 × 2 = 84/180 - Likewise, for the 2nd fraction, since 12 × 15 = 180,
81/12 = 81 × 15/12 × 15 = 1215/180 - Subtract the two like fractions:
84/180 - 1215/180 = 84 - 1215/180 = -1131/180 - After reducing the fraction, the answer is -377/60
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