Add 12/21 and 30/18, Solve 12/21 + 1 12/18 as a fraction

Add 12/21 and 30/18

1^st number: 12/21, 2^nd number: 1 12/18

12/21 + 30/18 is 47/21.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 18 is 126

Next, find the equivalent fraction of both fractional numbers with denominator 126
For the 1st fraction, since 21 × 6 = 126,
12/21 = 12 × 6/21 × 6 = 72/126
Likewise, for the 2nd fraction, since 18 × 7 = 126,
30/18 = 30 × 7/18 × 7 = 210/126
Add the two like fractions:
72/126 + 210/126 = 72 + 210/126 = 282/126
282/126 simplified gives 47/21
So, 12/21 + 30/18 = 47/21
In mixed form: 25/21

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