Add 5/21 and 72/54, Solve 5/21 + 1 18/54 as a fraction

Add 5/21 and 72/54

1^st number: 5/21, 2^nd number: 1 18/54

5/21 + 72/54 is 11/7.

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,
5/21 = 5 × 18/21 × 18 = 90/378
Likewise, for the 2nd fraction, since 54 × 7 = 378,
72/54 = 72 × 7/54 × 7 = 504/378
Add the two like fractions:
90/378 + 504/378 = 90 + 504/378 = 594/378
594/378 simplified gives 11/7
So, 5/21 + 72/54 = 11/7
In mixed form: 14/7

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