Subtract 10/4 from 81/42
1st number: 1 39/42, 2nd number: 2 2/4
81/42 - 10/4 is -4/7.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 4 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 42 × 2 = 84,
81/42 = 81 × 2/42 × 2 = 162/84 - Likewise, for the 2nd fraction, since 4 × 21 = 84,
10/4 = 10 × 21/4 × 21 = 210/84 - Subtract the two like fractions:
162/84 - 210/84 = 162 - 210/84 = -48/84 - After reducing the fraction, the answer is -4/7
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