Add 21/9 and 54/8, Solve 2 3/9 + 6 6/8 as a fraction

Add 21/9 and 54/8

1^st number: 2 3/9, 2^nd number: 6 6/8

21/9 + 54/8 is 109/12.

Find the least common denominator or LCM of the two denominators:
LCM of 9 and 8 is 72

Next, find the equivalent fraction of both fractional numbers with denominator 72
For the 1st fraction, since 9 × 8 = 72,
21/9 = 21 × 8/9 × 8 = 168/72
Likewise, for the 2nd fraction, since 8 × 9 = 72,
54/8 = 54 × 9/8 × 9 = 486/72
Add the two like fractions:
168/72 + 486/72 = 168 + 486/72 = 654/72
654/72 simplified gives 109/12
So, 21/9 + 54/8 = 109/12
In mixed form: 91/12

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