149999 to the nearest hundred thousand
54999
It is 75 when rounded to the nearest whole number
The largest number you can get before rounding into 45,000 would be 44,999. The only way to get something larger than that would to be use decimal places after the final three 9s. So 44,999 is the largest whole number.
As an estimate of a whole number it can be rounded to 528
The answer will depend on the degree to which the number is rounded. Without any indication of that, it is not possible to answer the question sensibly.
149999 to the nearest hundred thousand
849 is the largest whole number that can be rounded to 800.
The largest whole number would be 1,999
750000 to 849999
5000
54999.
54999
0
8000
600
It could be 599, rounded to the nearest 400.
100