800
Because it is 800 4 is below 5 which mean that it can't be round off to make the hundred go up one. Now, if you had 853 then it will be 900.
It is 800.
If you look to the right of the hundreds place, it is a 4.
If it's 4 or under go down, if it's 5 or higher go up.
Since it's 4, we go down, so we get 800.
843 rounded to the nearest hundred is 800. We look at the units digit, which is 3, and since it's less than 5, we round down. Therefore, we keep the hundreds place as is and change the tens and units to zero.
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