Add 15/21 and 21/9, Solve 15/21 + 2 3/9 as a fraction

Add 15/21 and 21/9

1^st number: 15/21, 2^nd number: 2 3/9

15/21 + 21/9 is 64/21.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 9 is 63

Next, find the equivalent fraction of both fractional numbers with denominator 63
For the 1st fraction, since 21 × 3 = 63,
15/21 = 15 × 3/21 × 3 = 45/63
Likewise, for the 2nd fraction, since 9 × 7 = 63,
21/9 = 21 × 7/9 × 7 = 147/63
Add the two like fractions:
45/63 + 147/63 = 45 + 147/63 = 192/63
192/63 simplified gives 64/21
So, 15/21 + 21/9 = 64/21
In mixed form: 31/21

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