The average weight of the 2006 starting four defensive linemen of the Jacksonville Jaguars is 297 pounds. What is this weight in kilograms?

Question

I have the answer key so I know the answer but I don't know how to get there. For one, my teacher came up with his own conversion factor which I am struggling with. For example, he has the following scribbled down:

297lb x 1kg/2.20lb = 135kg

That's his solution to the answer. Now I understand how he set it up, but I do not understand where he obtain 2.20lb as his conversion factor. In my chart there is no such thing. I am so confused when it comes to conversion factors. Please help me understand where the 2.20lb come from.

Answer 1

That's just what it is. Like 1 foot = 12 inches. And 1 yard = 3 feet. These are conversion factors that have to be memorized/learned or looked up. In this case, the conversion is that 1 kilogram is equal to 2.2 pounds.

Then just use dimensional analysis where you set it up so that units cancel, leaving you with what you want. Here you want kg, so you want lbs to cancel.

297 lbs x 1 kg/2.20 lbs = 135 kg