Add 90/7 and 21/9, Solve 12 6/7 + 2 3/9 as a fraction

Add 90/7 and 21/9

1^st number: 12 6/7, 2^nd number: 2 3/9

90/7 + 21/9 is 319/21.

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,
90/7 = 90 × 9/7 × 9 = 810/63
Likewise, for the 2nd fraction, since 9 × 7 = 63,
21/9 = 21 × 7/9 × 7 = 147/63
Add the two like fractions:
810/63 + 147/63 = 810 + 147/63 = 957/63
957/63 simplified gives 319/21
So, 90/7 + 21/9 = 319/21
In mixed form: 154/21

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