Add 81/80 and 56/70, Solve 1 1/80 + 56/70 as a fraction

Add 81/80 and 56/70

1^st number: 1 1/80, 2^nd number: 56/70

81/80 + 56/70 is 29/16.

Find the least common denominator or LCM of the two denominators:
LCM of 80 and 70 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 70 × 8 = 560,
56/70 = 56 × 8/70 × 8 = 448/560
Add the two like fractions:
567/560 + 448/560 = 567 + 448/560 = 1015/560
1015/560 simplified gives 29/16
So, 81/80 + 56/70 = 29/16
In mixed form: 113/16

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