Add 21/4 and 12/9, Solve 5 1/4 + 1 3/9 as a fraction

Add 21/4 and 12/9

1^st number: 5 1/4, 2^nd number: 1 3/9

21/4 + 12/9 is 79/12.

Find the least common denominator or LCM of the two denominators:
LCM of 4 and 9 is 36

Next, find the equivalent fraction of both fractional numbers with denominator 36
For the 1st fraction, since 4 × 9 = 36,
21/4 = 21 × 9/4 × 9 = 189/36
Likewise, for the 2nd fraction, since 9 × 4 = 36,
12/9 = 12 × 4/9 × 4 = 48/36
Add the two like fractions:
189/36 + 48/36 = 189 + 48/36 = 237/36
237/36 simplified gives 79/12
So, 21/4 + 12/9 = 79/12
In mixed form: 67/12

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