The total number of keys for the back door of the house with a green sticker is 9.
The total number of keys for all doors with a green sticker is 4 + 9 = 13.
Therefore, the probability that a randomly selected key is labeled with a green sticker and opens the back door of the house is 9/13.
While visiting her grandparents, Isabelle found a box with a surprising number of spare keys. Isabelle figured that the color of the sticker on each key must indicate what the key was for. When Isabelle tested the keys, she was surprised to find that this was not the case.
Front door of the house Back door of the house
Blue sticker 1 5
Green sticker 4 9
What is the probability that a randomly selected key is labeled with a green sticker and opens the back door of the house?
Simplify any fractions.
1 answer