How much is 3 1/2 pounds written as. a combination of whole pounds and whole ounces

Well, since 1 pound is 16 ounces, half of a pound is 8 ounces. It says in the question that 3 1/2 is the number being used (tell me if that is not clear) so your answer would be 3 pounds and 8 ounces. If you want it only in ounces, then you could do 16x3+8, which is 46 ounces.

3.5 pound = 3 5/10 pounds = 3 1/2 pounds

1 pound = 16 ounces, 1/2 pound = 16*1/2 = 8 oz

Your answer should be 3 pounds and 8 oz.