Answer:
4.1
Explanation:
When rounding up decimals, if it is 5 or greater than 5, add 1 to the left decimal and if it is less than 5, leave the left decimal as it is.
In 4.06, the decimal digit 6 is greater than 5 so we add 1 to the left decimal digit which is 0 and 4.06 becomes 4.1