Add 30/21 and 21/18, Solve 1 9/21 + 1 3/18 as a fraction

Add 30/21 and 21/18

1^st number: 1 9/21, 2^nd number: 1 3/18

30/21 + 21/18 is 109/42.

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,
30/21 = 30 × 6/21 × 6 = 180/126
Likewise, for the 2nd fraction, since 18 × 7 = 126,
21/18 = 21 × 7/18 × 7 = 147/126
Add the two like fractions:
180/126 + 147/126 = 180 + 147/126 = 327/126
327/126 simplified gives 109/42
So, 30/21 + 21/18 = 109/42
In mixed form: 225/42

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