Add 9/21 and 84/18, Solve 9/21 + 4 12/18 as a fraction

Add 9/21 and 84/18

1^st number: 9/21, 2^nd number: 4 12/18

9/21 + 84/18 is 107/21.

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,
9/21 = 9 × 6/21 × 6 = 54/126
Likewise, for the 2nd fraction, since 18 × 7 = 126,
84/18 = 84 × 7/18 × 7 = 588/126
Add the two like fractions:
54/126 + 588/126 = 54 + 588/126 = 642/126
642/126 simplified gives 107/21
So, 9/21 + 84/18 = 107/21
In mixed form: 52/21

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