2.6 is already rounded to the nearest tenth.
If the original answer was 2.67345, it would be rounded to 2.7.
or
if it were 2.63421; it would be 2.6
The number after a decimal; (2.6 is the tenth)
816.45 = hundred
816.45 = ten
816.45 = one
816.45 = tenth
816.45 = hundredth