Subtract 81/30 from 28/20
1st number: 1 8/20, 2nd number: 2 21/30
28/20 - 81/30 is -13/10.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 30 is 60
Next, find the equivalent fraction of both fractional numbers with denominator 60 - For the 1st fraction, since 20 × 3 = 60,
28/20 = 28 × 3/20 × 3 = 84/60 - Likewise, for the 2nd fraction, since 30 × 2 = 60,
81/30 = 81 × 2/30 × 2 = 162/60 - Subtract the two like fractions:
84/60 - 162/60 = 84 - 162/60 = -78/60 - After reducing the fraction, the answer is -13/10
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