Add 15/4 and 21/27, Solve 3 3/4 + 21/27 as a fraction

Add 15/4 and 21/27

1^st number: 3 3/4, 2^nd number: 21/27

15/4 + 21/27 is 163/36.

Find the least common denominator or LCM of the two denominators:
LCM of 4 and 27 is 108

Next, find the equivalent fraction of both fractional numbers with denominator 108
For the 1st fraction, since 4 × 27 = 108,
15/4 = 15 × 27/4 × 27 = 405/108
Likewise, for the 2nd fraction, since 27 × 4 = 108,
21/27 = 21 × 4/27 × 4 = 84/108
Add the two like fractions:
405/108 + 84/108 = 405 + 84/108 = 489/108
489/108 simplified gives 163/36
So, 15/4 + 21/27 = 163/36
In mixed form: 419/36

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