Add 70/9 and 21/63, Solve 7 7/9 + 21/63 as a fraction

Add 70/9 and 21/63

1^st number: 7 7/9, 2^nd number: 21/63

70/9 + 21/63 is 73/9.

Find the least common denominator or LCM of the two denominators:
LCM of 9 and 63 is 63

Next, find the equivalent fraction of both fractional numbers with denominator 63
For the 1st fraction, since 9 × 7 = 63,
70/9 = 70 × 7/9 × 7 = 490/63
Likewise, for the 2nd fraction, since 63 × 1 = 63,
21/63 = 21 × 1/63 × 1 = 21/63
Add the two like fractions:
490/63 + 21/63 = 490 + 21/63 = 511/63
511/63 simplified gives 73/9
So, 70/9 + 21/63 = 73/9
In mixed form: 81/9

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