The average height of five men is 68 inches. If one man is 70 inches tall and three other have an average of 67 inches, the height of the fifth amn, in inches, is:
If a pipe can fill a tank in 2 hours and another pipe can fill the same tank in 40 minutes. how much time in minutes is needed to fill the tank if both the pipes are working together?
A rectangular lot 50 feet by 100 feet is surrounded on all sides by a concrete walk 5 feet wide. Find the number of square feet in the surface of the walk.
In solving an arithmetic example, Donna, by mistake multiplied by 6 instead of dividing by 6. If her anser was 13 1/5, what should be the correct answer to the example ?