Add 12/9 and 42/12, Solve 1 3/9 + 3 6/12 as a fraction

Add 12/9 and 42/12

1^st number: 1 3/9, 2^nd number: 3 6/12

12/9 + 42/12 is 29/6.

Find the least common denominator or LCM of the two denominators:
LCM of 9 and 12 is 36

Next, find the equivalent fraction of both fractional numbers with denominator 36
For the 1st fraction, since 9 × 4 = 36,
12/9 = 12 × 4/9 × 4 = 48/36
Likewise, for the 2nd fraction, since 12 × 3 = 36,
42/12 = 42 × 3/12 × 3 = 126/36
Add the two like fractions:
48/36 + 126/36 = 48 + 126/36 = 174/36
174/36 simplified gives 29/6
So, 12/9 + 42/12 = 29/6
In mixed form: 45/6

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