When 20 cartons failed to be delivered, the number of cartons reduced to 50-20 = <<50-20=30>>30 cartons.
The total number of jars in all the cartons is 30*20 = <<30*20=600>>600
The total number of jars destroyed in the 5 cartons is 3*5 = <<3*5=15>>15 jars.
If one carton was also destroyed, the total number of destroyed jars is 20+15 = <<20+15=35>>35 jars.
The number of jars good for sale is 600-35 = <<600-35=565>>565 jars.
#### 565