You would write the 80.5 on the outside 418.6 on the inside. You can't divide by a decimal so you have to move the decimal point as many times as you need to on the outside number. You only have to move it over once in the80.5 so it is now 805. You do the same thing to the inside so it it is 4186. You are now dividing 4186 by 805. The answer is 5.2