Subtract 9/84 from 81/42
1st number: 1 39/42, 2nd number: 9/84
81/42 - 9/84 is 51/28.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 84 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 84 × 1 = 84,
9/84 = 9 × 1/84 × 1 = 9/84 - Subtract the two like fractions:
162/84 - 9/84 = 162 - 9/84 = 153/84 - After reducing the fraction, the answer is 51/28
- In mixed form: 123/28
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