Add 90/81 and 21/63, Solve 1 9/81 + 21/63 as a fraction

Add 90/81 and 21/63

1^st number: 1 9/81, 2^nd number: 21/63

90/81 + 21/63 is 13/9.

Find the least common denominator or LCM of the two denominators:
LCM of 81 and 63 is 567

Next, find the equivalent fraction of both fractional numbers with denominator 567
For the 1st fraction, since 81 × 7 = 567,
90/81 = 90 × 7/81 × 7 = 630/567
Likewise, for the 2nd fraction, since 63 × 9 = 567,
21/63 = 21 × 9/63 × 9 = 189/567
Add the two like fractions:
630/567 + 189/567 = 630 + 189/567 = 819/567
819/567 simplified gives 13/9
So, 90/81 + 21/63 = 13/9
In mixed form: 14/9

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