Decimal numbers are based on . letters (a and b) 16 digits 10 digits two digits (1s and 0s)

10 digits.

Explanation:

Decimal numbers are based on 10 digits.

Simply stated, decimal numbers comprises of the digits ranging from 0 to 9 i.e 0, 1, 2, 3, 4, 5, 6, 7, 8 and 9. Thus, all decimal numbers are solely dependent on the aforementioned 10 digits.

Hence, decimal numbers are considered to be a normal (standard) number system because they are based on 10 digits (0 through 9) and as such they are the numbers used in our everyday life across the world.

This ultimately implies that, any normal number to be written as decimal numbers can only use or combine the 10 digits (0 - 9).

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