Apainter leans a 20-ft ladder against a building. the base of the ladder is 12 ft from the building. to the nearest foot, how high on the building does the ladder reach?

The perimeter of a stage is 116 feet. it is 17 feet wide. how long is it?

The lengths of all sides of a triangle are integers when measured in decimeters. one of the sides has length of 1 dm and another of 3 dm. find the perimeter of the triangle.'

At the beginning of 1974/75,2 years a man invested #2000 in a bank at 12.5% compound interest, if it degree #650 at the end of each two years to pay his son's school fees, after payment of interest to pay his son's school fees, how much did he have left at the beginning of the 1978/79 school year?