Subtract 28/18 from 21/20
1st number: 1 1/20, 2nd number: 1 10/18
21/20 - 28/18 is -91/180.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 18 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 20 × 9 = 180,
21/20 = 21 × 9/20 × 9 = 189/180 - Likewise, for the 2nd fraction, since 18 × 10 = 180,
28/18 = 28 × 10/18 × 10 = 280/180 - Subtract the two like fractions:
189/180 - 280/180 = 189 - 280/180 = -91/180
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