Add 5/42 and 63/18, Solve 5/42 + 3 9/18 as a fraction

Add 5/42 and 63/18

1^st number: 5/42, 2^nd number: 3 9/18

5/42 + 63/18 is 76/21.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 18 is 126

Next, find the equivalent fraction of both fractional numbers with denominator 126
For the 1st fraction, since 42 × 3 = 126,
5/42 = 5 × 3/42 × 3 = 15/126
Likewise, for the 2nd fraction, since 18 × 7 = 126,
63/18 = 63 × 7/18 × 7 = 441/126
Add the two like fractions:
15/126 + 441/126 = 15 + 441/126 = 456/126
456/126 simplified gives 76/21
So, 5/42 + 63/18 = 76/21
In mixed form: 313/21

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