Add 84/72 and 21/9, Solve 1 12/72 + 2 3/9 as a fraction

Add 84/72 and 21/9

1^st number: 1 12/72, 2^nd number: 2 3/9

84/72 + 21/9 is 7/2.

Find the least common denominator or LCM of the two denominators:
LCM of 72 and 9 is 72

Next, find the equivalent fraction of both fractional numbers with denominator 72
For the 1st fraction, since 72 × 1 = 72,
84/72 = 84 × 1/72 × 1 = 84/72
Likewise, for the 2nd fraction, since 9 × 8 = 72,
21/9 = 21 × 8/9 × 8 = 168/72
Add the two like fractions:
84/72 + 168/72 = 84 + 168/72 = 252/72
252/72 simplified gives 7/2
So, 84/72 + 21/9 = 7/2
In mixed form: 31/2

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