There are 1200 trees in an apple orchard. The owner randomly examined 20 trees and found 3 of them are infested. What is the expected number of infested trees in the orchard?
Using the ratio, 180 of them are infected. Probably. It's just the expected value.
Hope this Helps.... :P
Or, Using a tiny probabilty, the Famer just found 3/3 infected trees, but 180 infected has my best bets.
If 3/20 trees are infested and there are 1200 trees total, then 3/20*1200=180 so there should be around 180 infested trees.
You are very welcome!