Subtract 81/60 from 18/30
1st number: 18/30, 2nd number: 1 21/60
18/30 - 81/60 is -3/4.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 60 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 60 × 1 = 60,
81/60 = 81 × 1/60 × 1 = 81/60 - Subtract the two like fractions:
36/60 - 81/60 = 36 - 81/60 = -45/60 - After reducing the fraction, the answer is -3/4
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