Subtract 72/20 from 1/18
1st number: 1/18, 2nd number: 3 12/20
1/18 - 72/20 is -319/90.
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,
1/18 = 1 × 10/18 × 10 = 10/180 - Likewise, for the 2nd fraction, since 20 × 9 = 180,
72/20 = 72 × 9/20 × 9 = 648/180 - Subtract the two like fractions:
10/180 - 648/180 = 10 - 648/180 = -638/180 - After reducing the fraction, the answer is -319/90
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