Add 28/21 and 15/12, Solve 1 7/21 + 1 3/12 as a fraction

Add 28/21 and 15/12

1^st number: 1 7/21, 2^nd number: 1 3/12

28/21 + 15/12 is 31/12.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 12 is 84

Next, find the equivalent fraction of both fractional numbers with denominator 84
For the 1st fraction, since 21 × 4 = 84,
28/21 = 28 × 4/21 × 4 = 112/84
Likewise, for the 2nd fraction, since 12 × 7 = 84,
15/12 = 15 × 7/12 × 7 = 105/84
Add the two like fractions:
112/84 + 105/84 = 112 + 105/84 = 217/84
217/84 simplified gives 31/12
So, 28/21 + 15/12 = 31/12
In mixed form: 27/12

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