66/71 as a percentage is 92.96%. This means the fraction is very close to a whole number, just a little bit under 100%.
The fraction 66/71 shows how many parts out of a total of 71 are taken. When you have 66 of those parts, you are holding a large majority of the whole.
Because the percentage is so high, you can think of 66/71 as almost a complete set. It’s useful in situations like scoring, where you want to see how much of a total was achieved.
In everyday language, saying something is 92.96% tells people quickly that it’s almost perfect, without having to work with the fraction directly.