Add 42/54 and 18/21
42/54 + 18/21 is 103/63.
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,
42/54 = 42 × 7/54 × 7 = 294/378 - Likewise, for the 2nd fraction, since 21 × 18 = 378,
18/21 = 18 × 18/21 × 18 = 324/378 - Add the two like fractions:
294/378 + 324/378 = 294 + 324/378 = 618/378 - 618/378 simplified gives 103/63
- So, 42/54 + 18/21 = 103/63
In mixed form: 140/63
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