Add 30/18 and 8/21, Solve 1 12/18 + 8/21 as a fraction

Add 30/18 and 8/21

1^st number: 1 12/18, 2^nd number: 8/21

30/18 + 8/21 is 43/21.

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

Next, find the equivalent fraction of both fractional numbers with denominator 126
For the 1st fraction, since 18 × 7 = 126,
30/18 = 30 × 7/18 × 7 = 210/126
Likewise, for the 2nd fraction, since 21 × 6 = 126,
8/21 = 8 × 6/21 × 6 = 48/126
Add the two like fractions:
210/126 + 48/126 = 210 + 48/126 = 258/126
258/126 simplified gives 43/21
So, 30/18 + 8/21 = 43/21
In mixed form: 21/21

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