Add 42/21 and 12/9, Solve 2 0/21 + 1 3/9 as a fraction

Add 42/21 and 12/9

1^st number: 2 0/21, 2^nd number: 1 3/9

42/21 + 12/9 is 10/3.

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,
42/21 = 42 × 3/21 × 3 = 126/63
Likewise, for the 2nd fraction, since 9 × 7 = 63,
12/9 = 12 × 7/9 × 7 = 84/63
Add the two like fractions:
126/63 + 84/63 = 126 + 84/63 = 210/63
210/63 simplified gives 10/3
So, 42/21 + 12/9 = 10/3
In mixed form: 31/3

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