Add 63/28 and 12/21, Solve 2 7/28 + 12/21 as a fraction

Add 63/28 and 12/21

1^st number: 2 7/28, 2^nd number: 12/21

63/28 + 12/21 is 79/28.

Find the least common denominator or LCM of the two denominators:
LCM of 28 and 21 is 84

Next, find the equivalent fraction of both fractional numbers with denominator 84
For the 1st fraction, since 28 × 3 = 84,
63/28 = 63 × 3/28 × 3 = 189/84
Likewise, for the 2nd fraction, since 21 × 4 = 84,
12/21 = 12 × 4/21 × 4 = 48/84
Add the two like fractions:
189/84 + 48/84 = 189 + 48/84 = 237/84
237/84 simplified gives 79/28
So, 63/28 + 12/21 = 79/28
In mixed form: 223/28

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