Sammy's pet dog weighs 10 pounds, and his pet caterpillar weighs 2 ounces. How many ounces less does his pet caterpillar weigh?

Change the 10 pounds to ounces so that the units are the same.

There are 16 ounces in a pound so 10 * 16 = 160 ounces.

160 - 2 = 158 ounces.

The caterpillar weighs 158 ounces less that the dog.

Let's call the objects objects 1 and 2.

Object #1 weighs 10 whatever.

Object #2 weights 2 whatever.

Here, now we subtract 2 from 10.

10-2 = 8.

Sammy's pet caterpillar weighs 8 ounces less than his pet dog.