A student was asked to round 80.13 to the nearest tens. Their answer was 70.
What mistake, if any did they make?
When rounding down, they dropped the number that should have stayed the same.
They just took off the extra numbers, rather than rounding.
They rounded using the last number instead of the number just to the right of the spot to round.
They didn't understand the difference between tens and tenths or hundreds and hundredths,
They didn't make a mistake.