Add 3/9 and 75/21, Solve 3/9 + 3 12/21 as a fraction

Add 3/9 and 75/21

1^st number: 3/9, 2^nd number: 3 12/21

3/9 + 75/21 is 82/21.

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

Next, find the equivalent fraction of both fractional numbers with denominator 63
For the 1st fraction, since 9 × 7 = 63,
3/9 = 3 × 7/9 × 7 = 21/63
Likewise, for the 2nd fraction, since 21 × 3 = 63,
75/21 = 75 × 3/21 × 3 = 225/63
Add the two like fractions:
21/63 + 225/63 = 21 + 225/63 = 246/63
246/63 simplified gives 82/21
So, 3/9 + 75/21 = 82/21
In mixed form: 319/21

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