Add 90/81 and 81/70, Solve 1 9/81 + 1 11/70 as a fraction

Add 90/81 and 81/70

1^st number: 1 9/81, 2^nd number: 1 11/70

90/81 + 81/70 is 1429/630.

Find the least common denominator or LCM of the two denominators:
LCM of 81 and 70 is 5670

Next, find the equivalent fraction of both fractional numbers with denominator 5670
For the 1st fraction, since 81 × 70 = 5670,
90/81 = 90 × 70/81 × 70 = 6300/5670
Likewise, for the 2nd fraction, since 70 × 81 = 5670,
81/70 = 81 × 81/70 × 81 = 6561/5670
Add the two like fractions:
6300/5670 + 6561/5670 = 6300 + 6561/5670 = 12861/5670
12861/5670 simplified gives 1429/630
So, 90/81 + 81/70 = 1429/630
In mixed form: 2169/630

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