What is 30 in a decimal?

Answer 1

In a decimal system, the number 30 is written as "30.0." The decimal point separates the whole number part (30) from the fractional part (0). The zero after the decimal point indicates that there are no tenths, hundredths, or thousandths in this particular number.

Answer 2

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 30, exactly as in the question.