Subtract 81/35 from 72/20
1st number: 3 12/20, 2nd number: 2 11/35
72/20 - 81/35 is 9/7.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 35 is 140
Next, find the equivalent fraction of both fractional numbers with denominator 140 - For the 1st fraction, since 20 × 7 = 140,
72/20 = 72 × 7/20 × 7 = 504/140 - Likewise, for the 2nd fraction, since 35 × 4 = 140,
81/35 = 81 × 4/35 × 4 = 324/140 - Subtract the two like fractions:
504/140 - 324/140 = 504 - 324/140 = 180/140 - After reducing the fraction, the answer is 9/7
- In mixed form: 12/7
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