Ways to Select Balls from Four Distinct Boxes
Consider 4 boxes, where each box contains 3 red balls and 2 blue balls. Assume that all 20 balls are distinct. In how many different ways can 10 balls be chosen from these 4 boxes so that from each box at least one red ball and one blue ball are chosen ?
Options
21816
85536
12096
156816
Topics & Concepts
Step-by-Step Solution
To find the total number of ways to select balls from distinct boxes such that at least one red ball and one blue ball are chosen from each box, let us analyze the possible selections from a single box.
Step 1: Ways to choose balls from a single box
Each box contains red balls and blue balls (all distinct).
Let be the number of red balls and be the number of blue balls chosen from a box. We are given and . The total number of balls chosen from one box is .
Let be the number of ways to select balls from a single box satisfying the condition:
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For :
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For :
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For :
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Step 2: Distribution of 10 balls among 4 boxes
Let be the number of balls selected from Box 1, Box 2, Box 3, and Box 4, respectively. We must have:
Let , where . Substituting this gives:
The possible integer distributions of are:
Case 1: One and three
This corresponds to selecting balls from the four boxes in some order.
- The number of ways to assign these counts to the 4 distinct boxes is:
- For each assignment, the number of ways to choose the balls is:
- Total ways for Case 1:
Case 2: Two and two
This corresponds to selecting balls from the four boxes in some order.
- The number of ways to assign these counts to the 4 distinct boxes is:
- For each assignment, the number of ways to choose the balls is:
- Total ways for Case 2:
Step 3: Total Number of Ways
Thus, the correct option is (A).