Subtract 72/20 from 21/9
1st number: 2 3/9, 2nd number: 3 12/20
21/9 - 72/20 is -19/15.
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,
21/9 = 21 × 20/9 × 20 = 420/180 - Likewise, for the 2nd fraction, since 20 × 9 = 180,
72/20 = 72 × 9/20 × 9 = 648/180 - Subtract the two like fractions:
420/180 - 648/180 = 420 - 648/180 = -228/180 - After reducing the fraction, the answer is -19/15
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