10.1, 20.1 , 30.1 are the decimal where the value of digit 1/10 had existed.
“Decimal” comes from the Latin root decem, which simply means “ten.” The number system we use is called the decimal number system, because the place value units go in tens: you have ones, tens, hundreds, thousands, and so on, each unit being 10 times the previous one.
In common language, the word “decimal number” has come to mean numbers which have digits after the decimal point, such as 5.8 or 9.302. But any number within the decimal number system could be designate a decimal number, involve whole numbers such as 12 or 381.
A Decimal Number (based on the number 10) contains a Decimal Point.
Here is the number "forty-five and six-tenths" written as a decimal number:
The decimal point goes between Ones and Tenths.
45.6 has 4 Tens, 5 Ones and 6 Tenths, like this:40+5+6/10
