Add 28/21 and 27/4, Solve 1 7/21 + 6 3/4 as a fraction

Add 28/21 and 27/4

1^st number: 1 7/21, 2^nd number: 6 3/4

28/21 + 27/4 is 97/12.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 4 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 4 × 21 = 84,
27/4 = 27 × 21/4 × 21 = 567/84
Add the two like fractions:
112/84 + 567/84 = 112 + 567/84 = 679/84
679/84 simplified gives 97/12
So, 28/21 + 27/4 = 97/12
In mixed form: 81/12

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