Subtract 72/20 from 18/90
1st number: 18/90, 2nd number: 3 12/20
18/90 - 72/20 is -17/5.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 20 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 90 × 2 = 180,
18/90 = 18 × 2/90 × 2 = 36/180 - Likewise, for the 2nd fraction, since 20 × 9 = 180,
72/20 = 72 × 9/20 × 9 = 648/180 - Subtract the two like fractions:
36/180 - 648/180 = 36 - 648/180 = -612/180 - After reducing the fraction, the answer is -17/5
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