3. Give the least number that can be rounded to the nearest ten thousand?

any number can be rounded to the nearest thousand or 10,000 or any other value.

Maybe you should be more specific...

4. Give the greatest numbr dat can be to the nearest thousand

To find the least number that can be rounded to the nearest ten thousand, we need to consider the values closer to both the smaller and larger side of ten thousand.

Since ten thousand is in the middle of the rounding range (i.e., halfway between the numbers 5,000 and 15,000), we need to identify the closest number to ten thousand on both sides.

Round-down Scenario:
To find the closest number smaller than ten thousand, we look for the largest multiple of ten thousand that is less than ten thousand.

The largest multiple of ten thousand less than ten thousand is zero. However, since we are asked for a non-zero value, we consider the number immediately after zero, which is one. Thus, the closest number smaller than ten thousand is one.

Round-up Scenario:
To find the closest number larger than ten thousand, we look for the smallest multiple of ten thousand that is greater than ten thousand.

The smallest multiple of ten thousand greater than ten thousand is ten thousand itself. Therefore, the closest number larger than ten thousand is ten thousand.

In conclusion, the least number that can be rounded to the nearest ten thousand is one.