Answer:
I suppose that you want to know how many pounds he expects to use.
He expects to use 48 oz.
We know that:
1lb = 16oz
then:
1 = (1lb/16 oz)
If we multiply any number by one, the number does not change, then:
48 oz = 48 oz*1 = 48 oz*( 1lb/16 oz) = (48oz/16oz)*1lb = 3 lb