Add 72/28 and 21/12, Solve 2 16/28 + 1 9/12 as a fraction

Add 72/28 and 21/12

1^st number: 2 16/28, 2^nd number: 1 9/12

72/28 + 21/12 is 121/28.

Find the least common denominator or LCM of the two denominators:
LCM of 28 and 12 is 84

Next, find the equivalent fraction of both fractional numbers with denominator 84
For the 1st fraction, since 28 × 3 = 84,
72/28 = 72 × 3/28 × 3 = 216/84
Likewise, for the 2nd fraction, since 12 × 7 = 84,
21/12 = 21 × 7/12 × 7 = 147/84
Add the two like fractions:
216/84 + 147/84 = 216 + 147/84 = 363/84
363/84 simplified gives 121/28
So, 72/28 + 21/12 = 121/28
In mixed form: 49/28

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