Igot 2a and 2b correct but i guessed the answers, how do i actually solve this type of question?

Know one knows how to actually answer a question everyone guesses until they actually learn it. at least you got them right

The problems are similar to a "play on words"  The population when around to the nearest 1,000th is 8,277,000, which by means of around the actual population is any where between 8,277,499 (which when rounding would be to round down or it could be 8,276,500, which would cause the population to around up to 8,277,000.

To get the high and the low, you take half of the rounded place value (in this case being 1000/2=500, and subtract it from the rounded number and then add it minus 1 from the rounded number (499).  If it was round to the near 100.  Then you would take 100/2= 50, so the numbers to get the max and min would be 50 and 49.