Add 81/21 and 27/6, Solve 3 18/21 + 4 3/6 as a fraction

Add 81/21 and 27/6

1^st number: 3 18/21, 2^nd number: 4 3/6

81/21 + 27/6 is 117/14.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 6 is 42

Next, find the equivalent fraction of both fractional numbers with denominator 42
For the 1st fraction, since 21 × 2 = 42,
81/21 = 81 × 2/21 × 2 = 162/42
Likewise, for the 2nd fraction, since 6 × 7 = 42,
27/6 = 27 × 7/6 × 7 = 189/42
Add the two like fractions:
162/42 + 189/42 = 162 + 189/42 = 351/42
351/42 simplified gives 117/14
So, 81/21 + 27/6 = 117/14
In mixed form: 85/14

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