Add 30/9 and 45/12, Solve 3 3/9 + 3 9/12 as a fraction

Add 30/9 and 45/12

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

30/9 + 45/12 is 85/12.

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,
30/9 = 30 × 4/9 × 4 = 120/36
Likewise, for the 2nd fraction, since 12 × 3 = 36,
45/12 = 45 × 3/12 × 3 = 135/36
Add the two like fractions:
120/36 + 135/36 = 120 + 135/36 = 255/36
255/36 simplified gives 85/12
So, 30/9 + 45/12 = 85/12
In mixed form: 71/12

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