Add 80/42 and 12/9, Solve 1 38/42 + 1 3/9 as a fraction

Add 80/42 and 12/9

1^st number: 1 38/42, 2^nd number: 1 3/9

80/42 + 12/9 is 68/21.

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,
80/42 = 80 × 3/42 × 3 = 240/126
Likewise, for the 2nd fraction, since 9 × 14 = 126,
12/9 = 12 × 14/9 × 14 = 168/126
Add the two like fractions:
240/126 + 168/126 = 240 + 168/126 = 408/126
408/126 simplified gives 68/21
So, 80/42 + 12/9 = 68/21
In mixed form: 35/21

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