780
The digit in the ones position is a 1, so we round down. That means 780 is the answer.
780
780
778 rounding to the nearest 10 is 780. The digit to the right of the tens is the ones. When rounding anything less than five you round down. When rounding anything five or more you round up. The ones digit is 8, which is more than 5, so you round up, making the answer 780.
800 is the nearest round hundred of 780.
The number 780 is already rounded to the nearest tenth.
790
The answer is 780
To the nearest ten, 780
780
800