A printer can produce 360 pages in 8 minutes. A second printer can produce 280 pages in 7 minutes. If both printers run together for 12 minutes, how many total pages do they produce?

A wildlife researcher tags 48 fish in a lake and releases them. One week later, the researcher catches a sample of 200 fish and finds that 12 of them are tagged. Using this proportion, what is the estimated total number of fish in the lake?

An athlete runs the first 6 kilometers of a race at 12 kilometers per hour and the remaining 4 kilometers at 8 kilometers per hour. What is the athlete's average speed, in kilometers per hour, for the entire race?

A scale model of a building is built at a ratio of 1:150. If a room in the model has a floor area of 8 square inches, what is the actual floor area of the room, in square inches?

A tank is being filled by two pipes. Pipe A fills the tank at a rate of 3 gallons per minute, and Pipe B fills it at 5 gallons per minute. At the same time, a drain removes water at 2 gallons per minute. If the tank holds 240 gallons, how many minutes will it take to fill the tank from empty?

A laboratory technician needs to prepare 500 milliliters of a 30% saline solution by mixing a 20% saline solution with a 50% saline solution. How many milliliters of the 50% solution are needed?

A delivery truck travels from City A to City B at 60 miles per hour and returns along the same route at 40 miles per hour. What is the truck's average speed, in miles per hour, for the entire round trip?