First, covert 3 pounds to ounces...then add the 2 ounces given. The weight of one jar, in ounces, is 50 ounces. Given that, multiply 320 by 50. The answer to that is 16,000. Therefore, there are 16,000 in 320 jars. To get the answer pack to pounds....divide 16,000 by 16 since there are 16 ounces in a pound. The answer would be 1,000 pounds. Meaning, there are 1,000 pounds OR 16,000 ounces in 320 jars. Hope this helps :)