Subtract 81/36 from 42/30
1st number: 1 12/30, 2nd number: 2 9/36
42/30 - 81/36 is -17/20.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 36 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 30 × 6 = 180,
42/30 = 42 × 6/30 × 6 = 252/180 - Likewise, for the 2nd fraction, since 36 × 5 = 180,
81/36 = 81 × 5/36 × 5 = 405/180 - Subtract the two like fractions:
252/180 - 405/180 = 252 - 405/180 = -153/180 - After reducing the fraction, the answer is -17/20
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