Subtract 3/21 from 81/18
1st number: 4 9/18, 2nd number: 3/21
81/18 - 3/21 is 61/14.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 21 is 126
Next, find the equivalent fraction of both fractional numbers with denominator 126 - For the 1st fraction, since 18 × 7 = 126,
81/18 = 81 × 7/18 × 7 = 567/126 - Likewise, for the 2nd fraction, since 21 × 6 = 126,
3/21 = 3 × 6/21 × 6 = 18/126 - Subtract the two like fractions:
567/126 - 18/126 = 567 - 18/126 = 549/126 - After reducing the fraction, the answer is 61/14
- In mixed form: 45/14
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