Add 80/42 and 36/9, Solve 1 38/42 + 4 0/9 as a fraction

Add 80/42 and 36/9

1^st number: 1 38/42, 2^nd number: 4 0/9

80/42 + 36/9 is 124/21.

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,
36/9 = 36 × 14/9 × 14 = 504/126
Add the two like fractions:
240/126 + 504/126 = 240 + 504/126 = 744/126
744/126 simplified gives 124/21
So, 80/42 + 36/9 = 124/21
In mixed form: 519/21

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