Subtract 81/8 from 28/20
1st number: 1 8/20, 2nd number: 10 1/8
28/20 - 81/8 is -349/40.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 8 is 40
Next, find the equivalent fraction of both fractional numbers with denominator 40 - For the 1st fraction, since 20 × 2 = 40,
28/20 = 28 × 2/20 × 2 = 56/40 - Likewise, for the 2nd fraction, since 8 × 5 = 40,
81/8 = 81 × 5/8 × 5 = 405/40 - Subtract the two like fractions:
56/40 - 405/40 = 56 - 405/40 = -349/40
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