Add 12/21 and 30/54
12/21 + 30/54 is 71/63.
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,
12/21 = 12 × 18/21 × 18 = 216/378 - Likewise, for the 2nd fraction, since 54 × 7 = 378,
30/54 = 30 × 7/54 × 7 = 210/378 - Add the two like fractions:
216/378 + 210/378 = 216 + 210/378 = 426/378 - 426/378 simplified gives 71/63
- So, 12/21 + 30/54 = 71/63
In mixed form: 18/63
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