Subtract 7/42 from 81/12
1st number: 6 9/12, 2nd number: 7/42
81/12 - 7/42 is 79/12.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 42 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 12 × 7 = 84,
81/12 = 81 × 7/12 × 7 = 567/84 - Likewise, for the 2nd fraction, since 42 × 2 = 84,
7/42 = 7 × 2/42 × 2 = 14/84 - Subtract the two like fractions:
567/84 - 14/84 = 567 - 14/84 = 553/84 - After reducing the fraction, the answer is 79/12
- In mixed form: 67/12
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