Add 30/54 and 81/21
1st number: 30/54, 2nd number: 3 18/21
30/54 + 81/21 is 278/63.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 54 and 21 is 378
Next, find the equivalent fraction of both fractional numbers with denominator 378 - For the 1st fraction, since 54 × 7 = 378,
30/54 = 30 × 7/54 × 7 = 210/378 - Likewise, for the 2nd fraction, since 21 × 18 = 378,
81/21 = 81 × 18/21 × 18 = 1458/378 - Add the two like fractions:
210/378 + 1458/378 = 210 + 1458/378 = 1668/378 - 1668/378 simplified gives 278/63
- So, 30/54 + 81/21 = 278/63
In mixed form: 426/63
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