Add 81/80 and 63/35, Solve 1 1/80 + 1 28/35 as a fraction

Add 81/80 and 63/35

1^st number: 1 1/80, 2^nd number: 1 28/35

81/80 + 63/35 is 45/16.

Find the least common denominator or LCM of the two denominators:
LCM of 80 and 35 is 560

Next, find the equivalent fraction of both fractional numbers with denominator 560
For the 1st fraction, since 80 × 7 = 560,
81/80 = 81 × 7/80 × 7 = 567/560
Likewise, for the 2nd fraction, since 35 × 16 = 560,
63/35 = 63 × 16/35 × 16 = 1008/560
Add the two like fractions:
567/560 + 1008/560 = 567 + 1008/560 = 1575/560
1575/560 simplified gives 45/16
So, 81/80 + 63/35 = 45/16
In mixed form: 213/16

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