Add 20/42 and 12/9, Solve 20/42 + 1 3/9 as a fraction

Add 20/42 and 12/9

1^st number: 20/42, 2^nd number: 1 3/9

20/42 + 12/9 is 38/21.

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,
20/42 = 20 × 3/42 × 3 = 60/126
Likewise, for the 2nd fraction, since 9 × 14 = 126,
12/9 = 12 × 14/9 × 14 = 168/126
Add the two like fractions:
60/126 + 168/126 = 60 + 168/126 = 228/126
228/126 simplified gives 38/21
So, 20/42 + 12/9 = 38/21
In mixed form: 117/21

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