Add 21/42 and 35/54
21/42 + 35/54 is 31/27.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 54 is 378
Next, find the equivalent fraction of both fractional numbers with denominator 378 - For the 1st fraction, since 42 × 9 = 378,
21/42 = 21 × 9/42 × 9 = 189/378 - Likewise, for the 2nd fraction, since 54 × 7 = 378,
35/54 = 35 × 7/54 × 7 = 245/378 - Add the two like fractions:
189/378 + 245/378 = 189 + 245/378 = 434/378 - 434/378 simplified gives 31/27
- So, 21/42 + 35/54 = 31/27
In mixed form: 14/27
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