How many places does the decimal point move when you multiply a number by 10 and in which direction

Lorne subtracted 6x3 – 2x + 3 from –3x3 + 5x2 + 4x – 7. use the drop-down menus to identify the steps lorne used to find the difference.

How do you solve a question like this?

Sara can take no more than 22 pounds of luggage on a trip. her suitcase weighs 112 ounces. how many more pounds can she pack without going over the limit?