Subtract 81/12 from 18/30
1st number: 18/30, 2nd number: 6 9/12
18/30 - 81/12 is -123/20.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 12 is 60
Next, find the equivalent fraction of both fractional numbers with denominator 60 - For the 1st fraction, since 30 × 2 = 60,
18/30 = 18 × 2/30 × 2 = 36/60 - Likewise, for the 2nd fraction, since 12 × 5 = 60,
81/12 = 81 × 5/12 × 5 = 405/60 - Subtract the two like fractions:
36/60 - 405/60 = 36 - 405/60 = -369/60 - After reducing the fraction, the answer is -123/20
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