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

Add 81/70 and 70/90

1^st number: 1 11/70, 2^nd number: 70/90

81/70 + 70/90 is 1219/630.

Find the least common denominator or LCM of the two denominators:
LCM of 70 and 90 is 630

Next, find the equivalent fraction of both fractional numbers with denominator 630
For the 1st fraction, since 70 × 9 = 630,
81/70 = 81 × 9/70 × 9 = 729/630
Likewise, for the 2nd fraction, since 90 × 7 = 630,
70/90 = 70 × 7/90 × 7 = 490/630
Add the two like fractions:
729/630 + 490/630 = 729 + 490/630 = 1219/630
So, 81/70 + 70/90 = 1219/630
In mixed form: 1589/630

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