Add 72/21 and 30/6, Solve 3 9/21 + 5 0/6 as a fraction

Add 72/21 and 30/6

1^st number: 3 9/21, 2^nd number: 5 0/6

72/21 + 30/6 is 59/7.

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,
72/21 = 72 × 2/21 × 2 = 144/42
Likewise, for the 2nd fraction, since 6 × 7 = 42,
30/6 = 30 × 7/6 × 7 = 210/42
Add the two like fractions:
144/42 + 210/42 = 144 + 210/42 = 354/42
354/42 simplified gives 59/7
So, 72/21 + 30/6 = 59/7
In mixed form: 83/7

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