Add 30/21 and 12/9, Solve 1 9/21 + 1 3/9 as a fraction

Add 30/21 and 12/9

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

30/21 + 12/9 is 58/21.

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,
30/21 = 30 × 3/21 × 3 = 90/63
Likewise, for the 2nd fraction, since 9 × 7 = 63,
12/9 = 12 × 7/9 × 7 = 84/63
Add the two like fractions:
90/63 + 84/63 = 90 + 84/63 = 174/63
174/63 simplified gives 58/21
So, 30/21 + 12/9 = 58/21
In mixed form: 216/21

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