Step 1: Probability that the first card is King. \[ P(\text{1st is King}) = \frac{4}{52} = \frac{1}{13} \]
Step 2: Probability that the second card is also King. After one King is drawn, 3 Kings remain and 51 cards are left. \[ P(\text{2nd is King}) = \frac{3}{51} = \frac{1}{17} \]
Step 3: Probability that the third card is Ace. Now, 50 cards remain (4 Aces still there). \[ P(\text{3rd is Ace}) = \frac{4}{50} = \frac{2}{25} \]
Step 4: Multiply probabilities (independent successive events). \[ P(\text{First two Kings and third Ace}) = \frac{1}{13} \times \frac{1}{17} \times \frac{2}{25} \] \[ = \frac{2}{5525} \]
Final Answer: \[ \boxed{\dfrac{2}{5525}} \]
Of the 20 lightbulbs in a box, 2 are defective. An inspector will select 2 lightbulbs simultaneously and at random from the box. What is the probability that neither of the lightbulbs selected will be defective?