What percentage to use? ALL OF THEM...
Just training ( for example) triples at 80% is just as unproductive as 10's at 45% or singles at 95%...
Every week you can make progress in some way by doing more reps at a certain weight, more weight at a certain rep range, more speed at a certain weight, more sets at a rep or weight,or less rest between sets.
By improving any one of these variables each week you can slowly but surely make progress.
Train reps at a lighter percentage one week, speed at a medium percentage the next, and heavy singles for a new max the next. They all build strength.