4 cards are drawn from a well – shuffled deck of 52 cards. What is the probability of obtaining 3 diamonds and one spade?
The probability of obtaining 3 diamonds and one spade is 286/20825.
Explanation
This question is from Miscellaneous Exercise on Chapter 14, Question 2. The solution follows the same approach as Example 10 in the textbook, which uses combinations to calculate probabilities when drawing multiple cards. We need to find favorable outcomes (choosing 3 diamonds from 13 and 1 spade from 13) divided by total possible outcomes (choosing 4 cards from 52).
Solution Steps
Step 1: Total number of possible outcomes when 4 cards are drawn from 52 cards = ⁵²C₄ = (×)/(×) = 270725
Step 2: Number of ways to choose 3 diamonds from 13 diamonds = ¹³C₃ = (×11)/(×1) = 286
Step 3: Number of ways to choose 1 spade from 13 spades = ¹³C₁ = 13
Step 4: Number of favorable outcomes = ¹³C₃ × ¹³C₁ = = 3718
Step 5: Required probability = 3718/270725 = 286/20825