Add 21/12 and 8/7, Solve 1 9/12 + 1 1/7 as a fraction

Add 21/12 and 8/7

1^st number: 1 9/12, 2^nd number: 1 1/7

21/12 + 8/7 is 81/28.

Find the least common denominator or LCM of the two denominators:
LCM of 12 and 7 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 7 × 12 = 84,
8/7 = 8 × 12/7 × 12 = 96/84
Add the two like fractions:
147/84 + 96/84 = 147 + 96/84 = 243/84
243/84 simplified gives 81/28
So, 21/12 + 8/7 = 81/28
In mixed form: 225/28

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