Add 72/21 and 27/84, Solve 3 9/21 + 27/84 as a fraction

Add 72/21 and 27/84

1^st number: 3 9/21, 2^nd number: 27/84

72/21 + 27/84 is 15/4.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 84 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 84 × 1 = 84,
27/84 = 27 × 1/84 × 1 = 27/84
Add the two like fractions:
288/84 + 27/84 = 288 + 27/84 = 315/84
315/84 simplified gives 15/4
So, 72/21 + 27/84 = 15/4
In mixed form: 33/4

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