To round a number:
If the number after number of decimal places is:
>5 you add a unit in the last decimal that fits in the number of decimals place
< 5 you leave the decimal as it is in the number that fits in the number of decimals place
As you need to round the given number two decimal places and the number after the two decimals is greather than 5, you add a unit in the seocnd decimal:
Then, 2.6666 rounded two decimal places is 2.67