Add 81/21 and 15/54
1st number: 3 18/21, 2nd number: 15/54
81/21 + 15/54 is 521/126.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 54 is 378
Next, find the equivalent fraction of both fractional numbers with denominator 378 - For the 1st fraction, since 21 × 18 = 378,
81/21 = 81 × 18/21 × 18 = 1458/378 - Likewise, for the 2nd fraction, since 54 × 7 = 378,
15/54 = 15 × 7/54 × 7 = 105/378 - Add the two like fractions:
1458/378 + 105/378 = 1458 + 105/378 = 1563/378 - 1563/378 simplified gives 521/126
- So, 81/21 + 15/54 = 521/126
In mixed form: 417/126
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