Add 21/27 and 63/18, Solve 21/27 + 3 9/18 as a fraction

Add 21/27 and 63/18

1^st number: 21/27, 2^nd number: 3 9/18

21/27 + 63/18 is 77/18.

Find the least common denominator or LCM of the two denominators:
LCM of 27 and 18 is 54

Next, find the equivalent fraction of both fractional numbers with denominator 54
For the 1st fraction, since 27 × 2 = 54,
21/27 = 21 × 2/27 × 2 = 42/54
Likewise, for the 2nd fraction, since 18 × 3 = 54,
63/18 = 63 × 3/18 × 3 = 189/54
Add the two like fractions:
42/54 + 189/54 = 42 + 189/54 = 231/54
231/54 simplified gives 77/18
So, 21/27 + 63/18 = 77/18
In mixed form: 45/18

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