Add 21/4 and 63/3, Solve 5 1/4 + 21 0/3 as a fraction

Add 21/4 and 63/3

1^st number: 5 1/4, 2^nd number: 21 0/3

21/4 + 63/3 is 105/4.

Find the least common denominator or LCM of the two denominators:
LCM of 4 and 3 is 12

Next, find the equivalent fraction of both fractional numbers with denominator 12
For the 1st fraction, since 4 × 3 = 12,
21/4 = 21 × 3/4 × 3 = 63/12
Likewise, for the 2nd fraction, since 3 × 4 = 12,
63/3 = 63 × 4/3 × 4 = 252/12
Add the two like fractions:
63/12 + 252/12 = 63 + 252/12 = 315/12
315/12 simplified gives 105/4
So, 21/4 + 63/3 = 105/4
In mixed form: 261/4

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