Subtract 81/42 from 63/18
1st number: 3 9/18, 2nd number: 1 39/42
63/18 - 81/42 is 11/7.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 42 is 126
Next, find the equivalent fraction of both fractional numbers with denominator 126 - For the 1st fraction, since 18 × 7 = 126,
63/18 = 63 × 7/18 × 7 = 441/126 - Likewise, for the 2nd fraction, since 42 × 3 = 126,
81/42 = 81 × 3/42 × 3 = 243/126 - Subtract the two like fractions:
441/126 - 243/126 = 441 - 243/126 = 198/126 - After reducing the fraction, the answer is 11/7
- In mixed form: 14/7
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