The conversation between human and AI assistant.
[|Human|] Calculate the area of a 20 foot by 40 foot pool.
[|AI|] The area of a pool with length 40 feet and width 20 feet is calculated by multiplying the length and the width. 

Area = Length x Width
Area = 40 ft x 20 ft

Therefore, the area of the pool is 800 square feet.
[|Human|] 
Calculate the area of a 20 foot by 40 foot pool.