Add 21/42 and 30/9, Solve 21/42 + 3 3/9 as a fraction

Add 21/42 and 30/9

1^st number: 21/42, 2^nd number: 3 3/9

21/42 + 30/9 is 23/6.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 9 is 126

Next, find the equivalent fraction of both fractional numbers with denominator 126
For the 1st fraction, since 42 × 3 = 126,
21/42 = 21 × 3/42 × 3 = 63/126
Likewise, for the 2nd fraction, since 9 × 14 = 126,
30/9 = 30 × 14/9 × 14 = 420/126
Add the two like fractions:
63/126 + 420/126 = 63 + 420/126 = 483/126
483/126 simplified gives 23/6
So, 21/42 + 30/9 = 23/6
In mixed form: 35/6

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