If there are 1000 grams in a kilogram and 545 grams in a pound, how many pounds are there per kilogram? round to the nearest tenth of a pound .

The appropriate conversion factor here is

545 grams
= 1
 1 lb

Let's change over to kg:

545 grams     1 kg
* = 0.545 kg/lb.  We were asked "how many pounds are 
 1 lb              1000 g                       there per lb?  To obtain this, invert
                                                       0.545 kg/lb:

      1 lb
= 1.83 lb/kg
 0.545 kg/lb