Subtract 81/28 from 81/20
1st number: 4 1/20, 2nd number: 2 25/28
81/20 - 81/28 is 81/70.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 28 is 140
Next, find the equivalent fraction of both fractional numbers with denominator 140 - For the 1st fraction, since 20 × 7 = 140,
81/20 = 81 × 7/20 × 7 = 567/140 - Likewise, for the 2nd fraction, since 28 × 5 = 140,
81/28 = 81 × 5/28 × 5 = 405/140 - Subtract the two like fractions:
567/140 - 405/140 = 567 - 405/140 = 162/140 - After reducing the fraction, the answer is 81/70
- In mixed form: 111/70
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