Add 8/21 and 84/63, Solve 8/21 + 1 21/63 as a fraction

Add 8/21 and 84/63

1^st number: 8/21, 2^nd number: 1 21/63

8/21 + 84/63 is 12/7.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 63 is 63

Next, find the equivalent fraction of both fractional numbers with denominator 63
For the 1st fraction, since 21 × 3 = 63,
8/21 = 8 × 3/21 × 3 = 24/63
Likewise, for the 2nd fraction, since 63 × 1 = 63,
84/63 = 84 × 1/63 × 1 = 84/63
Add the two like fractions:
24/63 + 84/63 = 24 + 84/63 = 108/63
108/63 simplified gives 12/7
So, 8/21 + 84/63 = 12/7
In mixed form: 15/7

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