Add 30/18 and 21/42, Solve 1 12/18 + 21/42 as a fraction

Add 30/18 and 21/42

1^st number: 1 12/18, 2^nd number: 21/42

30/18 + 21/42 is 13/6.

Find the least common denominator or LCM of the two denominators:
LCM of 18 and 42 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 42 × 3 = 126,
21/42 = 21 × 3/42 × 3 = 63/126
Add the two like fractions:
210/126 + 63/126 = 210 + 63/126 = 273/126
273/126 simplified gives 13/6
So, 30/18 + 21/42 = 13/6
In mixed form: 21/6

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