How to do conversion factors in a word problem. I'm Bon Crowder with MathFour.com, and we're talking about conversion factors. Suppose your word problem asks to convert 27 inches in to feet. So what we want is the inches to feet conversion factor which is the same as saying one foot is 12 inches and what we want is to convert this to the number one because we can't actually change the value of 27 inches, we still need 27 inches but we want it measured in feet. So we're going to look at either one foot over 12 inches if we spell that right is the number one or 12 inches over one foot is also the number one. We can treat this like the big fat one. Either one. So I'm going to multiply 27 by one of these clever forms of one. So I have 27 inches times and I want inches to cancel out so I want inches on the bottom and feet on the top so I want one foot over 12 inches. When I multiply across the top and the bottom you'll notice that my inches get to cancel and I have 27 times one which is 27 feet over 12. 27 over 12 if you do the arithmetic is 2.25 feet. You might not want it just in feet either so maybe you want it in two feet three inches. And that's how you convert feet to inches and do any conversion factors in a world problem. I'm Bon Crowder with MathFour.com. Enjoy.