Add 81/18 and 4/21, Solve 4 9/18 + 4/21 as a fraction

Add 81/18 and 4/21

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

81/18 + 4/21 is 197/42.

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,
81/18 = 81 × 7/18 × 7 = 567/126
Likewise, for the 2nd fraction, since 21 × 6 = 126,
4/21 = 4 × 6/21 × 6 = 24/126
Add the two like fractions:
567/126 + 24/126 = 567 + 24/126 = 591/126
591/126 simplified gives 197/42
So, 81/18 + 4/21 = 197/42
In mixed form: 429/42

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