Subtract 81/7 from 28/42
1st number: 28/42, 2nd number: 11 4/7
28/42 - 81/7 is -229/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 7 is 42
Next, find the equivalent fraction of both fractional numbers with denominator 42 - For the 1st fraction, since 42 × 1 = 42,
28/42 = 28 × 1/42 × 1 = 28/42 - Likewise, for the 2nd fraction, since 7 × 6 = 42,
81/7 = 81 × 6/7 × 6 = 486/42 - Subtract the two like fractions:
28/42 - 486/42 = 28 - 486/42 = -458/42 - After reducing the fraction, the answer is -229/21
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