Subtract 81/28 from 15/20
1st number: 15/20, 2nd number: 2 25/28
15/20 - 81/28 is -15/7.
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,
15/20 = 15 × 7/20 × 7 = 105/140 - Likewise, for the 2nd fraction, since 28 × 5 = 140,
81/28 = 81 × 5/28 × 5 = 405/140 - Subtract the two like fractions:
105/140 - 405/140 = 105 - 405/140 = -300/140 - After reducing the fraction, the answer is -15/7
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