45 rounded to the nearest ten is 50. When rounding to the nearest ten, we use the following rules:
- We round the number up to the nearest ten if the last digit in the number is 5, 6, 7, 8, or 9.
- We round the number down to the nearest ten if the last digit in the number is 1, 2, 3, or 4.
- If the last digit is 0, then we do not have to do any rounding, because it is already to the ten.
Therefore, since 45 ends in 5, we round it up to the nearest ten, which is 50.
