Add 12/21 and 42/54
12/21 + 42/54 is 85/63.
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,
42/54 = 42 × 7/54 × 7 = 294/378 - Add the two like fractions:
216/378 + 294/378 = 216 + 294/378 = 510/378 - 510/378 simplified gives 85/63
- So, 12/21 + 42/54 = 85/63
In mixed form: 122/63
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