Add 21/42 and 35/9, Solve 21/42 + 3 8/9 as a fraction

Add 21/42 and 35/9

1^st number: 21/42, 2^nd number: 3 8/9

21/42 + 35/9 is 79/18.

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,
35/9 = 35 × 14/9 × 14 = 490/126
Add the two like fractions:
63/126 + 490/126 = 63 + 490/126 = 553/126
553/126 simplified gives 79/18
So, 21/42 + 35/9 = 79/18
In mixed form: 47/18

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