Assuming this a rectangular prism, we will use the formula V=lwh to help us. V stands for Volume, l is the length, w is the width, and h is the height. If we know the Volume is 40 cubic units and the width is 2 units and the height is 5 units, we will put in the formula what we know. 40 cubic units = length times 2 units times 5 units. To find the missing factor, we will divide 40 by 10 (2 times 5). This gives us a length of 4 units.
