Add 7/21 and 42/54
7/21 + 42/54 is 10/9.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 54 is 378
Next, find the equivalent fraction of both fractional numbers with denominator 378 - For the 1st fraction, since 21 × 18 = 378,
7/21 = 7 × 18/21 × 18 = 126/378 - Likewise, for the 2nd fraction, since 54 × 7 = 378,
42/54 = 42 × 7/54 × 7 = 294/378 - Add the two like fractions:
126/378 + 294/378 = 126 + 294/378 = 420/378 - 420/378 simplified gives 10/9
- So, 7/21 + 42/54 = 10/9
In mixed form: 11/9
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