Add 36/12 and 21/84, Solve 3 0/12 + 21/84 as a fraction

Add 36/12 and 21/84

1^st number: 3 0/12, 2^nd number: 21/84

36/12 + 21/84 is 13/4.

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

Next, find the equivalent fraction of both fractional numbers with denominator 84
For the 1st fraction, since 12 × 7 = 84,
36/12 = 36 × 7/12 × 7 = 252/84
Likewise, for the 2nd fraction, since 84 × 1 = 84,
21/84 = 21 × 1/84 × 1 = 21/84
Add the two like fractions:
252/84 + 21/84 = 252 + 21/84 = 273/84
273/84 simplified gives 13/4
So, 36/12 + 21/84 = 13/4
In mixed form: 31/4

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