Unit 6 Contents

15. In the base-ten number system, you can fit only one of the digits 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 in each place. Do you think you might ever need to write more than one digit in a place? Explain.
16. Johnny had a number with 4 hundreds, 12 tens, and 5 ones. He wrote it like this: 4125. Is he correct? What would you tell him?

Comparing Number Systems

Not all number systems use place value. The Roman Numeral System uses a different way to represent numbers. Ones, tens, hundreds, and so on are shown by special symbols instead of special locations. Here are a few Roman Numerals:

• 

To show 3 hundreds in the Roman Numeral System, write the symbol C for one hundred 3 times: CCC. To show 2 tens, write the symbol X for ten 2 times: XX.

Here is the number 321 written in Roman Numerals:

• 

17. Write each number in the table below using base-ten shorthand and Roman Numerals. Compare the representations. How are they alike? How are they different?