Each of the digits in the number 4568923 is arranged in ascending order from left to right. The position of how many digits will remain unchanged as compared to that in the original number?

Question

Prepp Team · Accepted Answer

Analyzing Digit Positions After Sorting

The original number provided is 4568923.

Original Digit Positions

We list the digits and their initial positions in the number:

1st position: 4
2nd position: 5
3rd position: 6
4th position: 8
5th position: 9
6th position: 2
7th position: 3

Ascending Order Arrangement

The digits present in the number are {4, 5, 6, 8, 9, 2, 3}.

Sorting these digits in ascending order, we get the sequence: {2, 3, 4, 5, 6, 8, 9}.

This sorted sequence implies the following positions:

1st position: 2
2nd position: 3
3rd position: 4
4th position: 5
5th position: 6
6th position: 8
7th position: 9

Comparing Positions

Now, we compare the digit in each position before and after sorting:

Position 1: Original digit was 4, new digit is 2. (Changed)
Position 2: Original digit was 5, new digit is 3. (Changed)
Position 3: Original digit was 6, new digit is 4. (Changed)
Position 4: Original digit was 8, new digit is 5. (Changed)
Position 5: Original digit was 9, new digit is 6. (Changed)
Position 6: Original digit was 2, new digit is 8. (Changed)
Position 7: Original digit was 3, new digit is 9. (Changed)

Final Count of Unchanged Digits

By comparing the original positions with the positions after arranging the digits in ascending order, we find that no digit remains in its original place.

Therefore, the number of digits whose positions remain unchanged is 0.