Add 63/42 and 6/80, Solve 1 21/42 + 6/80 as a fraction

Add 63/42 and 6/80

1^st number: 1 21/42, 2^nd number: 6/80

63/42 + 6/80 is 63/40.

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,
6/80 = 6 × 21/80 × 21 = 126/1680
Add the two like fractions:
2520/1680 + 126/1680 = 2520 + 126/1680 = 2646/1680
2646/1680 simplified gives 63/40
So, 63/42 + 6/80 = 63/40
In mixed form: 123/40

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