Add 84/18 and 5/21, Solve 4 12/18 + 5/21 as a fraction

Add 84/18 and 5/21

1^st number: 4 12/18, 2^nd number: 5/21

84/18 + 5/21 is 103/21.

Find the least common denominator or LCM of the two denominators:
LCM of 18 and 21 is 126

Next, find the equivalent fraction of both fractional numbers with denominator 126
For the 1st fraction, since 18 × 7 = 126,
84/18 = 84 × 7/18 × 7 = 588/126
Likewise, for the 2nd fraction, since 21 × 6 = 126,
5/21 = 5 × 6/21 × 6 = 30/126
Add the two like fractions:
588/126 + 30/126 = 588 + 30/126 = 618/126
618/126 simplified gives 103/21
So, 84/18 + 5/21 = 103/21
In mixed form: 419/21

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