Add 28/21 and 28/12, Solve 1 7/21 + 2 4/12 as a fraction

Add 28/21 and 28/12

1^st number: 1 7/21, 2^nd number: 2 4/12

28/21 + 28/12 is 11/3.

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,
28/12 = 28 × 7/12 × 7 = 196/84
Add the two like fractions:
112/84 + 196/84 = 112 + 196/84 = 308/84
308/84 simplified gives 11/3
So, 28/21 + 28/12 = 11/3
In mixed form: 32/3

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