Add 63/42 and 4/80, Solve 1 21/42 + 4/80 as a fraction

Add 63/42 and 4/80

1^st number: 1 21/42, 2^nd number: 4/80

63/42 + 4/80 is 31/20.

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,
4/80 = 4 × 21/80 × 21 = 84/1680
Add the two like fractions:
2520/1680 + 84/1680 = 2520 + 84/1680 = 2604/1680
2604/1680 simplified gives 31/20
So, 63/42 + 4/80 = 31/20
In mixed form: 111/20

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