Add 80/42 and 90/63, Solve 1 38/42 + 1 27/63 as a fraction

Add 80/42 and 90/63

1^st number: 1 38/42, 2^nd number: 1 27/63

80/42 + 90/63 is 10/3.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 63 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 63 × 2 = 126,
90/63 = 90 × 2/63 × 2 = 180/126
Add the two like fractions:
240/126 + 180/126 = 240 + 180/126 = 420/126
420/126 simplified gives 10/3
So, 80/42 + 90/63 = 10/3
In mixed form: 31/3

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