It would be rounded to 60 if you're rounding to the nearest 10.
Numbers such as this are rounded down if the end digit is 1 to 4 and rounded up if the end digit is 5 to 9. So, 55, 56, 57, 58 and 59 would be rounded up to 60. 60 is unchanged. 61, 62, 63 and 64 would be rounded down to 60. The number is therefore any number from 55 to 64 inclusive.
60
60
rounded down
3.5 can be rounded up to 4 or down to 3, most often it will be rounded up.
60
The nearest hundred above 55 is 100. The nearest hundred below 55 is 0.
Numbers such as this are rounded down if the end digit is 1 to 4 and rounded up if the end digit is 5 to 9. So, 55, 56, 57, 58 and 59 would be rounded up to 60. 60 is unchanged. 61, 62, 63 and 64 would be rounded down to 60. The number is therefore any number from 55 to 64 inclusive.
60
60
60
60
rounded down
3.5 can be rounded up to 4 or down to 3, most often it will be rounded up.
It is 41 if rounded up. Or 40 if rounded down.
55 rounded to nearest ten is 60
Not that I'm aware of. Schools would round up or down the third number (such as 3.493 would be rounded down to 3.49, and 3.496 would be rounded up to 3.50)