Add 21/54 and 63/42
1st number: 21/54, 2nd number: 1 21/42
21/54 + 63/42 is 17/9.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 54 and 42 is 378
Next, find the equivalent fraction of both fractional numbers with denominator 378 - For the 1st fraction, since 54 × 7 = 378,
21/54 = 21 × 7/54 × 7 = 147/378 - Likewise, for the 2nd fraction, since 42 × 9 = 378,
63/42 = 63 × 9/42 × 9 = 567/378 - Add the two like fractions:
147/378 + 567/378 = 147 + 567/378 = 714/378 - 714/378 simplified gives 17/9
- So, 21/54 + 63/42 = 17/9
In mixed form: 18/9
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