Add 5/21 and 21/9, Solve 5/21 + 2 3/9 as a fraction

Add 5/21 and 21/9

1^st number: 5/21, 2^nd number: 2 3/9

5/21 + 21/9 is 18/7.

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,
5/21 = 5 × 3/21 × 3 = 15/63
Likewise, for the 2nd fraction, since 9 × 7 = 63,
21/9 = 21 × 7/9 × 7 = 147/63
Add the two like fractions:
15/63 + 147/63 = 15 + 147/63 = 162/63
162/63 simplified gives 18/7
So, 5/21 + 21/9 = 18/7
In mixed form: 24/7

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