Add 5/21 and 63/18, Solve 5/21 + 3 9/18 as a fraction

Add 5/21 and 63/18

1^st number: 5/21, 2^nd number: 3 9/18

5/21 + 63/18 is 157/42.

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,
5/21 = 5 × 6/21 × 6 = 30/126
Likewise, for the 2nd fraction, since 18 × 7 = 126,
63/18 = 63 × 7/18 × 7 = 441/126
Add the two like fractions:
30/126 + 441/126 = 30 + 441/126 = 471/126
471/126 simplified gives 157/42
So, 5/21 + 63/18 = 157/42
In mixed form: 331/42

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