Add 4/7 and 21/9, Solve 4/7 + 2 3/9 as a fraction

Add 4/7 and 21/9

1^st number: 4/7, 2^nd number: 2 3/9

4/7 + 21/9 is 61/21.

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,
4/7 = 4 × 9/7 × 9 = 36/63
Likewise, for the 2nd fraction, since 9 × 7 = 63,
21/9 = 21 × 7/9 × 7 = 147/63
Add the two like fractions:
36/63 + 147/63 = 36 + 147/63 = 183/63
183/63 simplified gives 61/21
So, 4/7 + 21/9 = 61/21
In mixed form: 219/21

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