Find the greatest common factor of 15/40

Which equation represents a proportional relationship that has a constant of proportionality equal to 1/5

Astore has clearance items that have been marked down by 60%. they are having a sale, advertising an additional 55% off clearance items. what percent of the original price do you end up paying?

If chord ab is congruent to chord cd, then what must be true about ef and eg?