Any number above 50 will be rounded up while 49 or less will be rounded down. Since 75 > 50, it will be rounded up.
Therefore, it will be rounded to 300
300
It is 300 when rounded to the nearest hundred
916 rounded to the nearest hundred is 900
0
It is already rounded to the nearest hundred thousandths. Rounded to the nearest thousands would be 87.381.
0
0
678 is rounded nearest hundred is 700
0
300
10900
500