Add 63/42 and 12/80, Solve 1 21/42 + 12/80 as a fraction

Add 63/42 and 12/80

1^st number: 1 21/42, 2^nd number: 12/80

63/42 + 12/80 is 33/20.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 80 is 1680

Next, find the equivalent fraction of both fractional numbers with denominator 1680
For the 1st fraction, since 42 × 40 = 1680,
63/42 = 63 × 40/42 × 40 = 2520/1680
Likewise, for the 2nd fraction, since 80 × 21 = 1680,
12/80 = 12 × 21/80 × 21 = 252/1680
Add the two like fractions:
2520/1680 + 252/1680 = 2520 + 252/1680 = 2772/1680
2772/1680 simplified gives 33/20
So, 63/42 + 12/80 = 33/20
In mixed form: 113/20

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