Subtract 81/42 from 5/28
1st number: 5/28, 2nd number: 1 39/42
5/28 - 81/42 is -7/4.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 42 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 28 × 3 = 84,
5/28 = 5 × 3/28 × 3 = 15/84 - Likewise, for the 2nd fraction, since 42 × 2 = 84,
81/42 = 81 × 2/42 × 2 = 162/84 - Subtract the two like fractions:
15/84 - 162/84 = 15 - 162/84 = -147/84 - After reducing the fraction, the answer is -7/4
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