Add 63/80 and 84/63, Solve 63/80 + 1 21/63 as a fraction

Add 63/80 and 84/63

1^st number: 63/80, 2^nd number: 1 21/63

63/80 + 84/63 is 509/240.

Find the least common denominator or LCM of the two denominators:
LCM of 80 and 63 is 5040

Next, find the equivalent fraction of both fractional numbers with denominator 5040
For the 1st fraction, since 80 × 63 = 5040,
63/80 = 63 × 63/80 × 63 = 3969/5040
Likewise, for the 2nd fraction, since 63 × 80 = 5040,
84/63 = 84 × 80/63 × 80 = 6720/5040
Add the two like fractions:
3969/5040 + 6720/5040 = 3969 + 6720/5040 = 10689/5040
10689/5040 simplified gives 509/240
So, 63/80 + 84/63 = 509/240
In mixed form: 229/240

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