Add 72/21 and 12/30, Solve 3 9/21 + 12/30 as a fraction

Add 72/21 and 12/30

1^st number: 3 9/21, 2^nd number: 12/30

72/21 + 12/30 is 134/35.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 30 is 210

Next, find the equivalent fraction of both fractional numbers with denominator 210
For the 1st fraction, since 21 × 10 = 210,
72/21 = 72 × 10/21 × 10 = 720/210
Likewise, for the 2nd fraction, since 30 × 7 = 210,
12/30 = 12 × 7/30 × 7 = 84/210
Add the two like fractions:
720/210 + 84/210 = 720 + 84/210 = 804/210
804/210 simplified gives 134/35
So, 72/21 + 12/30 = 134/35
In mixed form: 329/35

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