Add 21/54 and 28/21
1st number: 21/54, 2nd number: 1 7/21
21/54 + 28/21 is 31/18.
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,
21/54 = 21 × 7/54 × 7 = 147/378 - Likewise, for the 2nd fraction, since 21 × 18 = 378,
28/21 = 28 × 18/21 × 18 = 504/378 - Add the two like fractions:
147/378 + 504/378 = 147 + 504/378 = 651/378 - 651/378 simplified gives 31/18
- So, 21/54 + 28/21 = 31/18
In mixed form: 113/18
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