How many 4-inches by 8-inche bricks are needed to build a walk 6ft wide and 24 feet long?

You need 648 bricks. Convert 6 feet into 72 inches times by 24 feet converted to 288 inches which equal 20,736 square inches. A 4 x 8 inch brick is 32 square inches. Now take 20,736 inches and divide that by 32 which equals 648.