Logan's father receives 50 cartons delivery for his milk business, each carton having 20 jars of milk. On a particular week, he received 20 cartons less when the delivery was done, and during offloading, he realized 3 jars in 5 cartons each was damaged, and one carton was totally damaged. How many jars of milk were good for sale that week?
Please reason step by step, and put your final answer within \boxed{}.
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