Add 63/12 and 42/18, Solve 5 3/12 + 2 6/18 as a fraction

Add 63/12 and 42/18

1^st number: 5 3/12, 2^nd number: 2 6/18

63/12 + 42/18 is 91/12.

Find the least common denominator or LCM of the two denominators:
LCM of 12 and 18 is 36

Next, find the equivalent fraction of both fractional numbers with denominator 36
For the 1st fraction, since 12 × 3 = 36,
63/12 = 63 × 3/12 × 3 = 189/36
Likewise, for the 2nd fraction, since 18 × 2 = 36,
42/18 = 42 × 2/18 × 2 = 84/36
Add the two like fractions:
189/36 + 84/36 = 189 + 84/36 = 273/36
273/36 simplified gives 91/12
So, 63/12 + 42/18 = 91/12
In mixed form: 77/12

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