363 rounded to the nearest hundred is 400.
When you round a number to a certain digit, you have to check the value of the digit before the place you want to round off to.
Here, the question said nearest hundred, so I had to look at the value in the tens place that is 6.
If the number you are rounding is followed by 5, 6, 7, 8, or 9, round the number up. Example: 38 rounded to the nearest ten is 40.
If the number you are rounding is followed by 0, 1, 2, 3, or 4, round the number down. Example: 33 rounded to the nearest ten is 30.
