If the numbers in the tens and units equal less than 50, then you round down. If they are 50 or above, then you round down. So 312 rounds down to 300.
312 rounded to the nearest 100 (hundreds place) is 300.
It is 300 when rounded to the nearest hundred
916 rounded to the nearest hundred is 900
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It is already rounded to the nearest hundred thousandths. Rounded to the nearest thousands would be 87.381.
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678 is rounded nearest hundred is 700
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