Add 21/12 and 3/18, Solve 1 9/12 + 3/18 as a fraction

Add 21/12 and 3/18

1^st number: 1 9/12, 2^nd number: 3/18

21/12 + 3/18 is 23/12.

Find the least common denominator or LCM of the two denominators:
LCM of 12 and 18 is 36

Next, find the equivalent fraction of both fractional numbers with denominator 36
For the 1st fraction, since 12 × 3 = 36,
21/12 = 21 × 3/12 × 3 = 63/36
Likewise, for the 2nd fraction, since 18 × 2 = 36,
3/18 = 3 × 2/18 × 2 = 6/36
Add the two like fractions:
63/36 + 6/36 = 63 + 6/36 = 69/36
69/36 simplified gives 23/12
So, 21/12 + 3/18 = 23/12
In mixed form: 111/12

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