Add 21/54 and 9/7, Solve 21/54 + 1 2/7 as a fraction

Add 21/54 and 9/7

1^st number: 21/54, 2^nd number: 1 2/7

21/54 + 9/7 is 211/126.

Find the least common denominator or LCM of the two denominators:
LCM of 54 and 7 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 7 × 54 = 378,
9/7 = 9 × 54/7 × 54 = 486/378
Add the two like fractions:
147/378 + 486/378 = 147 + 486/378 = 633/378
633/378 simplified gives 211/126
So, 21/54 + 9/7 = 211/126
In mixed form: 185/126

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