Subtract 18/9 from 21/20
1st number: 1 1/20, 2nd number: 2 0/9
21/20 - 18/9 is -19/20.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 9 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 9 × 20 = 180,
18/9 = 18 × 20/9 × 20 = 360/180 - Subtract the two like fractions:
189/180 - 360/180 = 189 - 360/180 = -171/180 - After reducing the fraction, the answer is -19/20
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