What is 5,789,725 rounded to the nearest thousand

The answer depends on the third digit to the right (the hundreds digit). So, since the number in the 3rd digit is higher than five, it automatically rounds the next digit up, making the number 5,790,000.
5,790,000

5,789,725
The thousands place is 9, so let's look at the digit preceding it, a 7. A 7 is >= 5, therefore we round the 9 up, and we get 5,790,000.

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