Acell phone store sold 450 newly released cell phones in 3 hours. this was 30% of the number of phones sold that day. how many newly released cell phones did the cell phone company sell that day?

You are at a restaurant and owe $38 for your meal. you want to leave a 20% tip. how much will your tip be?

You're locked out of your house. the only open window is on the second floor, 25 feet above the ground. there are bushes along the edge of the house, so you will need to place the ladder 10 feet from the house. what length ladder do you need to reach the window?

Delbert keeps track of total of the total number of points he earns on homework assignments, each of which is worth 60 points. at the end of the semester he has 810 points. write an equation for delbert’s average homework score a in terms of the number of assignments n.