Jam and the jars
Lovely, lovely jam
Jar a has a volume of 206.298 and will cost about $11.90.
Jar B has a volume of 17.25 and will cost about 16 cents
If you buy the amount of jar B that equals the amount of volume of jar A you will be spending and average of 5 cents on buying the jar or more on packaging and shipping .
Buying in bulk
If you buy in bulk with less jars to package and ship you will be profiting from buying a lot of small jars.
The overall decision
Jar A is a better choice if you are wanting to ship and sell on large bulks