When rounding 2000 to the nearest 1000, you look at the hundreds place, which is 0. Since 0 is less than 5, you round down to the nearest thousand. Therefore, 2000 rounded to the nearest 1000 is 1000.
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1678 to the nearest 1000 would be 2000. This is because 1678 is closer to 2000 than it is to 1000. When rounding to the nearest 1000, you look at the hundreds place - in this case, the hundreds place is 6, which is closer to 10 (in 2000) than to 0 (in 1000).
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2000.
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