70% of the tickets sold at a water park were child tickets. If the park sold 80 tickets in all, how many child tickets did it sell?

Donald has x twenty-dollar bills and 11 ten-dollar bill. how much money does donald have? write your answer as an expression.

At oaknoll school, 90 out of 270 students on computers. what percent of students at oak knoll school do not own computers? round the nearest tenth of a percent.

An ant travels at a constant rate of 30cm every 2 minutes.at what speed does the ant travel per minute