Subtract 21/20 from 3/9
1st number: 3/9, 2nd number: 1 1/20
3/9 - 21/20 is -43/60.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 9 and 20 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 9 × 20 = 180,
3/9 = 3 × 20/9 × 20 = 60/180 - Likewise, for the 2nd fraction, since 20 × 9 = 180,
21/20 = 21 × 9/20 × 9 = 189/180 - Subtract the two like fractions:
60/180 - 189/180 = 60 - 189/180 = -129/180 - After reducing the fraction, the answer is -43/60
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