Add 72/21 and 45/12, Solve 3 9/21 + 3 9/12 as a fraction

Add 72/21 and 45/12

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

72/21 + 45/12 is 201/28.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 12 is 84

Next, find the equivalent fraction of both fractional numbers with denominator 84
For the 1st fraction, since 21 × 4 = 84,
72/21 = 72 × 4/21 × 4 = 288/84
Likewise, for the 2nd fraction, since 12 × 7 = 84,
45/12 = 45 × 7/12 × 7 = 315/84
Add the two like fractions:
288/84 + 315/84 = 288 + 315/84 = 603/84
603/84 simplified gives 201/28
So, 72/21 + 45/12 = 201/28
In mixed form: 75/28

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