710 as a decimal is the same as 710.0
You have already expressed it as a decimal.
7/10 = 0.7
710
710
1710.0
7/10 = 0.7
7.10 = 710%
7.10 = 710%
If you mean 2 and 7/10 then as a decimal it is 2.7
It is 710, as in the question. There is no need to add a decimal point. Adding a decimal point and one or more 0s is wrong because that implies a degree of precision that cannot be justified.
710 is an integer and so there is no sensible way of representing it as a mixed number.A decimal number is simply a way of representing a number in such a way that the place value of each digit is ten times that of the digit to its right. A decimal representation does not require a decimal point. So the required decimal representation is 710, exactly as in the question.