Subtract 21/20 from 18/30
1st number: 18/30, 2nd number: 1 1/20
18/30 - 21/20 is -9/20.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 20 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 20 × 3 = 60,
21/20 = 21 × 3/20 × 3 = 63/60 - Subtract the two like fractions:
36/60 - 63/60 = 36 - 63/60 = -27/60 - After reducing the fraction, the answer is -9/20
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