One piece of ribbon is 1 26/27 yards long, another is 8 5/7 yards long and the third is 12 5/9 yards long. What is the total number of yards?
You are going to have to find a common denominator for the fraction parts of those numbers before adding them.
The common denominator is 27x7 = 189
26/27 = 182/189
5/7 = 135/189
5/9 = 105/189
Sum of fractions 422/189 = 2 44/189
Add to that the sum of the integers 1,8 and 12 (=21). The answer is
23 44/189 yards
That is the exact answer. It is easier to do in decimal form and just round off. That would give you 23.2328...