0.895 rounded to the nearest hundred is 0.90.
Basic Rules of Rounding (from CalculatorSoup.com):
When we "round to the nearest ________", regardless of what goes in that blank the steps are nearly always the same:
Identify which place value we are rounding to. The smaller the place value, the more accurate the final result will be.
Look to the next smallest place value, or simply put, the one directly to the right of the place value we're rounding to. For example, if we want to round to the nearest ten, we will look at the ones place.
If this next smallest place value is less than five (0, 1, 2, 3, or 4), we leave the digit we want to round to alone. Any digits after that number (including the next smallest place value we just looked at) become zeros, or simply drop if after the decimal point. This is called rounding down.
If the next smallest place value is greater than or equal to five (5, 6, 7, 8, or 9), we increase the value of the digit we're rounding to by one. Just like before, any remaining digits before the decimal point become zeros, and any that are after the decimal point are dropped. This is called rounding up.
Estimating is an important part of mathematics and a very handy tool for everyday life. Get in the habit of estimating amounts of money, lengths of time, distances, and many other physical quantities.
And rounding off is a kind of estimating. Check out lessons on estimating and rounding on Math.com.