Add 21/18 and 10/7, Solve 1 3/18 + 1 3/7 as a fraction

Add 21/18 and 10/7

1^st number: 1 3/18, 2^nd number: 1 3/7

21/18 + 10/7 is 109/42.

Find the least common denominator or LCM of the two denominators:
LCM of 18 and 7 is 126

Next, find the equivalent fraction of both fractional numbers with denominator 126
For the 1st fraction, since 18 × 7 = 126,
21/18 = 21 × 7/18 × 7 = 147/126
Likewise, for the 2nd fraction, since 7 × 18 = 126,
10/7 = 10 × 18/7 × 18 = 180/126
Add the two like fractions:
147/126 + 180/126 = 147 + 180/126 = 327/126
327/126 simplified gives 109/42
So, 21/18 + 10/7 = 109/42
In mixed form: 225/42

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