SOLUTION: You carry six keys in your pocket, two of which are for the two locks on your front door. You lose one key. What is the probability that you can get into your house through the fro

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Question 1039386: You carry six keys in your pocket, two of which are for the two locks on your front door. You lose one key. What is the probability that you can get into your house through the front door?
Answer by Theo(13342) About Me  (Show Source):
You can put this solution on YOUR website!
losing one key is the same as randomly drawing one key out of the 6.

there are 2 keys in the set of 6 that you need to open the door.
there are 4 keys in the set of 6 that you don't need to open the door.

the probability that the key that you draw will not be one of the 2 keys that you need is therefore 4/6 = 2/3.

the probability that you can still get in your house is therefore 2/3 because that's the probability that the key that is lost is not one of the 2 keys that you need.