Add 21/72 and 63/12, Solve 21/72 + 5 3/12 as a fraction

Add 21/72 and 63/12

1^st number: 21/72, 2^nd number: 5 3/12

21/72 + 63/12 is 133/24.

Find the least common denominator or LCM of the two denominators:
LCM of 72 and 12 is 72

Next, find the equivalent fraction of both fractional numbers with denominator 72
For the 1st fraction, since 72 × 1 = 72,
21/72 = 21 × 1/72 × 1 = 21/72
Likewise, for the 2nd fraction, since 12 × 6 = 72,
63/12 = 63 × 6/12 × 6 = 378/72
Add the two like fractions:
21/72 + 378/72 = 21 + 378/72 = 399/72
399/72 simplified gives 133/24
So, 21/72 + 63/12 = 133/24
In mixed form: 513/24

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