Add 21/54 and 40/14, Solve 21/54 + 2 12/14 as a fraction

Add 21/54 and 40/14

1^st number: 21/54, 2^nd number: 2 12/14

21/54 + 40/14 is 409/126.

Find the least common denominator or LCM of the two denominators:
LCM of 54 and 14 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 14 × 27 = 378,
40/14 = 40 × 27/14 × 27 = 1080/378
Add the two like fractions:
147/378 + 1080/378 = 147 + 1080/378 = 1227/378
1227/378 simplified gives 409/126
So, 21/54 + 40/14 = 409/126
In mixed form: 331/126

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