Add 21/6 and 63/4, Solve 3 3/6 + 15 3/4 as a fraction

Add 21/6 and 63/4

1^st number: 3 3/6, 2^nd number: 15 3/4

21/6 + 63/4 is 77/4.

Find the least common denominator or LCM of the two denominators:
LCM of 6 and 4 is 12

Next, find the equivalent fraction of both fractional numbers with denominator 12
For the 1st fraction, since 6 × 2 = 12,
21/6 = 21 × 2/6 × 2 = 42/12
Likewise, for the 2nd fraction, since 4 × 3 = 12,
63/4 = 63 × 3/4 × 3 = 189/12
Add the two like fractions:
42/12 + 189/12 = 42 + 189/12 = 231/12
231/12 simplified gives 77/4
So, 21/6 + 63/4 = 77/4
In mixed form: 191/4

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