To round the numbers to the place value of the underlined digits, let's first identify each underlined digit and its corresponding place value:

1. 9,566,220: The underlined digit is 5.

   • Place Value: Hundreds of thousands (100,000).
   • Number: 9,566,220. To round to the nearest hundred thousand, we look at the digit in the ten thousand place, which is 6. Since it's 5 or higher, we round up.
   • Rounded Number: 9,600,000.

2. 3,000,866: The underlined digit is 8.

   • Place Value: Thousands (1,000).
   • Number: 3,000,866. To round to the nearest thousand, we look at the digit in the hundreds place, which is 8. Since it's 5 or higher, we round up.
   • Rounded Number: 3,001,000.

3. 824,530: The underlined digit is 5.

   • Place Value: Thousands (1,000).
   • Number: 824,530. To round to the nearest thousand, we look at the digit in the hundreds place, which is 5. Since it's 5 or higher, we round up.
   • Rounded Number: 825,000.

Would you like further details or have any other questions?

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Here are 8 related questions you might consider:

1. What is the difference between rounding to the nearest hundred thousand and nearest ten thousand?
2. How do you round a number to the nearest ten?
3. Can you explain how rounding differs from truncation?
4. How does rounding affect significant figures in a number?
5. What is the rule for rounding when the digit to the right is exactly 5?
6. How would you round the number 4,238 to the nearest hundred?
7. What is the process for rounding decimals to a specific decimal place?
8. How does rounding impact calculations in financial mathematics?

Tip: When rounding numbers, always pay attention to the digit immediately to the right of the place value you are rounding to. This digit determines whether you round up or stay the same.