Add 81/21 and 5/18
1st number: 3 18/21, 2nd number: 5/18
81/21 + 5/18 is 521/126.
Steps for adding 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,
5/18 = 5 × 7/18 × 7 = 35/126 - Add the two like fractions:
486/126 + 35/126 = 486 + 35/126 = 521/126 - So, 81/21 + 5/18 = 521/126
In mixed form: 417/126
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