An expert burglar has 8 master keys to open several new houses of a mansion.Only one master key will open a given house.If 40% of these houses remain unlocked the probability that the burglar will break open the treasury house on selecting 3 master keys at random is?
X: Home is unlocked=P(X)=25
Y:Home is locked:P(Y)=35
Z: Room gets opened by any of the 3 keys
P(Z)=P(Z intersection X)+P(Z intersection Y)