Arrange the following numbers in descending order :
190909, 1808088, 16060666, 16007777, 181888, 1808090

Answer

To arrange the numbers 190909, 1808088, 16060666, 16007777, 181888, and 1808090 in descending order, we will follow these steps:

### Step 1: Count the number of digits in each number.
- 190909 has 6 digits.
- 1808088 has 7 digits.
- 16060666 has 8 digits.
- 16007777 has 8 digits.
- 181888 has 6 digits.
- 1808090 has 7 digits.

### Step 2: Group the numbers based on the number of digits.
- **6-digit numbers**: 190909, 181888
- **7-digit numbers**: 1808088, 1808090
- **8-digit numbers**: 16060666, 16007777

### Step 3: Arrange the groups from largest to smallest based on the number of digits.
- The largest group is the 8-digit numbers.
- Next is the 7-digit numbers.
- The smallest group is the 6-digit numbers.

### Step 4: Compare the 8-digit numbers.
- 16060666 vs. 16007777
- Both have the same first digit (1), same second digit (6), but the third digit is different (0 vs. 0). Check the fourth digit: 6 vs. 0. Since 6 is greater than 0, 16060666 is larger.

### Step 5: Compare the 7-digit numbers.
- 1808088 vs. 1808090
- Both have the same first digit (1), second digit (8), and third digit (0). Check the fourth digit: 8 vs. 8. Check the fifth digit: 0 vs. 9. Since 9 is greater than 0, 1808090 is larger.

### Step 6: Compare the 6-digit numbers.
- 190909 vs. 181888
- Both have the same first digit (1). Check the second digit: 9 vs. 8. Since 9 is greater than 8, 190909 is larger.

### Step 7: Combine all the results in descending order.
- The order from largest to smallest is:
1. 16060666 (8 digits)
2. 16007777 (8 digits)
3. 1808090 (7 digits)
4. 1808088 (7 digits)
5. 190909 (6 digits)
6. 181888 (6 digits)

### Final Answer:
16060666, 16007777, 1808090, 1808088, 190909, 181888

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