Subtract 81/20 from 42/28
1st number: 1 14/28, 2nd number: 4 1/20
42/28 - 81/20 is -51/20.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 20 is 140
Next, find the equivalent fraction of both fractional numbers with denominator 140 - For the 1st fraction, since 28 × 5 = 140,
42/28 = 42 × 5/28 × 5 = 210/140 - Likewise, for the 2nd fraction, since 20 × 7 = 140,
81/20 = 81 × 7/20 × 7 = 567/140 - Subtract the two like fractions:
210/140 - 567/140 = 210 - 567/140 = -357/140 - After reducing the fraction, the answer is -51/20
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