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 5, exactly as in the question.
5.8 is already in decimal form!
2/5 = 0.4
0.8
4/5
5 in base ten is 101 binary (4 + 0 + 1).
5.0
5.8 is already in decimal form!
0.8
0.2
5/8 = 0.625
2.416666667.
12/5 = 2.4
2/5 = 0.4
0.8
14.8
4/5
5/8 = 0.625