Add 28/54 and 18/21
28/54 + 18/21 is 260/189.
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,
28/54 = 28 × 7/54 × 7 = 196/378 - Likewise, for the 2nd fraction, since 21 × 18 = 378,
18/21 = 18 × 18/21 × 18 = 324/378 - Add the two like fractions:
196/378 + 324/378 = 196 + 324/378 = 520/378 - 520/378 simplified gives 260/189
- So, 28/54 + 18/21 = 260/189
In mixed form: 171/189
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