Help me out I don’t understand

2men and 7 boys can do a piece of working 4 days. it is done by 4 men and 4 boys in 3 days how long would it take for 1man or one boy to do it alone

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?

Asurvey of 2,000 doctors showed that an average of 3 out of 5 doctors use brand x aspirin. how many doctors use brand x aspirin