At a particular school a study was conducted to see how many students brought their lunch from home. It was estimated that ! " of the student body brought their lunch. What percentage of the student body brought their lunch?

Serena is making an experiment. for that, she needs 20 grams of a 52% solution of salt. she has two large bottles of salt water: one with 40% and the other with 70% of salt in them. how much of each must she use to make the solution she needs? i am in need of