A rectangular pool is 50 feet long by 20 feet wide. The shallow end is 3 feet deep and the deep end is 7 feet deep. Find the surface area and the volume.
Surface Area = Length x Width
Surface Area = 50 feet x 20 feet
Surface Area = 1,000 square feet
Volume = Surface Area x Average Depth x 7.5
Volume = 1,000 x Average Depth x 7.5
Average Depth = (Shallow Depth + Deep Depth) ÷ 2
Average Depth = (3 + 7) ÷ 2
Average Depth = 10 ÷ 2
Average Depth = 5
Volume = 1,000 x 5 x 7.5
Volume = 37,500 Gallons