Puzzle ZDKN 

Workings

Hint
There are 3 feet in a yard, 1760 yards in a mile, and 8 furlongs in a mile.

Answer
Square feet in half a square mile.

Reasoning
There are 3 feet in a yard, 1760 yards in a mile, and 8 furlongs in a mile.

A mile is 1760 x 3 = 5280 feet in a mile.

A square mile is 5280 x 5280 = 27878400 square feet.

Therefore, half a square mile = 13,939,200 square feet.

A furlong is 1760 ÷ 8 = 220 yards.

Therefore, a cubic furlong is 220 x 220 x 220 = 10,648,000 cubic yards.