Subtract 70/18 from 72/20
1st number: 3 12/20, 2nd number: 3 16/18
72/20 - 70/18 is -13/45.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 18 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 20 × 9 = 180,
72/20 = 72 × 9/20 × 9 = 648/180 - Likewise, for the 2nd fraction, since 18 × 10 = 180,
70/18 = 70 × 10/18 × 10 = 700/180 - Subtract the two like fractions:
648/180 - 700/180 = 648 - 700/180 = -52/180 - After reducing the fraction, the answer is -13/45
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