Add 15/7 and 12/9, Solve 2 1/7 + 1 3/9 as a fraction

Add 15/7 and 12/9

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

15/7 + 12/9 is 73/21.

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,
15/7 = 15 × 9/7 × 9 = 135/63
Likewise, for the 2nd fraction, since 9 × 7 = 63,
12/9 = 12 × 7/9 × 7 = 84/63
Add the two like fractions:
135/63 + 84/63 = 135 + 84/63 = 219/63
219/63 simplified gives 73/21
So, 15/7 + 12/9 = 73/21
In mixed form: 310/21

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