Subtract 2/18 from 81/21
1st number: 3 18/21, 2nd number: 2/18
81/21 - 2/18 is 236/63.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 18 is 126
Next, find the equivalent fraction of both fractional numbers with denominator 126 - For the 1st fraction, since 21 × 6 = 126,
81/21 = 81 × 6/21 × 6 = 486/126 - Likewise, for the 2nd fraction, since 18 × 7 = 126,
2/18 = 2 × 7/18 × 7 = 14/126 - Subtract the two like fractions:
486/126 - 14/126 = 486 - 14/126 = 472/126 - After reducing the fraction, the answer is 236/63
- In mixed form: 347/63
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