Add 20/7 and 21/9, Solve 2 6/7 + 2 3/9 as a fraction

Add 20/7 and 21/9

1^st number: 2 6/7, 2^nd number: 2 3/9

20/7 + 21/9 is 109/21.

Find the least common denominator or LCM of the two denominators:
LCM of 7 and 9 is 63

Next, find the equivalent fraction of both fractional numbers with denominator 63
For the 1st fraction, since 7 × 9 = 63,
20/7 = 20 × 9/7 × 9 = 180/63
Likewise, for the 2nd fraction, since 9 × 7 = 63,
21/9 = 21 × 7/9 × 7 = 147/63
Add the two like fractions:
180/63 + 147/63 = 180 + 147/63 = 327/63
327/63 simplified gives 109/21
So, 20/7 + 21/9 = 109/21
In mixed form: 54/21

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