Everyone at your school has to take one art class, so 115 students take glass blowing, 90 students take cave painting, and 15 students take both. The wisest 120 students take photography for an easy A. How many total students are at your school?​

Liz is shipping a package to her friend.the maximum weight of a medium flat-rate box is 20 pounds,including the box which weighs 6 ounces.write and solve an inequality to describe the possible weight ,w, of the contents that liz will ship to her friend if she must use a medium flat-rate box.