Add 28/54 and 90/21
1st number: 28/54, 2nd number: 4 6/21
28/54 + 90/21 is 908/189.
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,
90/21 = 90 × 18/21 × 18 = 1620/378 - Add the two like fractions:
196/378 + 1620/378 = 196 + 1620/378 = 1816/378 - 1816/378 simplified gives 908/189
- So, 28/54 + 90/21 = 908/189
In mixed form: 4152/189
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