Subtract 21/20 from 12/18
1st number: 12/18, 2nd number: 1 1/20
12/18 - 21/20 is -23/60.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 20 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 18 × 10 = 180,
12/18 = 12 × 10/18 × 10 = 120/180 - Likewise, for the 2nd fraction, since 20 × 9 = 180,
21/20 = 21 × 9/20 × 9 = 189/180 - Subtract the two like fractions:
120/180 - 189/180 = 120 - 189/180 = -69/180 - After reducing the fraction, the answer is -23/60
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