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

Add 21/12 and 3/84

1^st number: 1 9/12, 2^nd number: 3/84

21/12 + 3/84 is 25/14.

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,
21/12 = 21 × 7/12 × 7 = 147/84
Likewise, for the 2nd fraction, since 84 × 1 = 84,
3/84 = 3 × 1/84 × 1 = 3/84
Add the two like fractions:
147/84 + 3/84 = 147 + 3/84 = 150/84
150/84 simplified gives 25/14
So, 21/12 + 3/84 = 25/14
In mixed form: 111/14

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