find the number of distinguishable permutations of the digits of the number 348 838.
How to find the number of distinguishable permutations of the digits of the number 348 838?
Answer:
To find the number of distinguishable permutations of the digits of a number like 348 838, we will follow the principles of combinatorics involving permutations of multiset (elements with repetition). Here’s how we do it step-by-step:
Step 1: Count the Total Digits
The given number is 348 838, which consists of six digits.
Step 2: Identify Frequency of Each Digit
In the number 348 838, the frequency of each digit is as follows:
- Digit ‘3’ appears 2 times
- Digit ‘4’ appears 1 time
- Digit ‘8’ appears 2 times
- Digit ‘8’ appears 3 times
Step 3: Apply the Permutation Formula for Multisets
The formula for finding the permutations of a multiset is:
\text{Number of permutations} = \frac{n!}{n_1! \times n_2! \times \cdots \times n_k!}
Where:
- ( n ) is the total number of elements (in this case, digits),
- ( n_1, n_2, \ldots, n_k ) are the frequencies of the distinguishable elements.
Step 4: Calculate the Permutations
Using the digits from 348 838, apply the formula:
- Total number of digits, ( n = 6 )
- Frequency of ‘3’ = 2
- Frequency of ‘4’ = 1
- Frequency of ‘8’ = 3
Applying these to the formula, we have:
\text{Number of permutations} = \frac{6!}{2! \times 1! \times 3!}
Now, calculate each factorial:
- ( 6! = 720 )
- ( 2! = 2 )
- ( 1! = 1 )
- ( 3! = 6 )
Plug these into the equation:
\text{Number of permutations} = \frac{720}{2 \times 1 \times 6} = \frac{720}{12} = 60
Final Answer:
The number of distinguishable permutations of the digits in the number 348 838 is 60.