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Place Value

Place Value Questions, a selection of answers from the Dr. Math archives.

Place Value - Units Digit

What is the units digit of 6100?

Writing Decimals from Words

Given a decimal written in words, how do you turn it into a decimal? In other words, how do you turn the words into numbers?

Writing Numbers in Words

Write each number in words: 1) 73.78007 2) 2.900087 (3) 34.4939.

Zeros after the Decimal Point

My students can't comprehend my explanation of how 3.70 is equivalent to 3.7 or 3.700 or 3.7000.

Which Place?

In which place is the digit 6 in the number 3164297 ?

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Place Value Chart

                0.000000001   one billionth

                0.00000001   one hundred-millionth
                0.0000001   one ten-millionth
                0.000001   one millionth

                0.00001   one hundred-thousandth
                0.0001   one ten-thousandth
                0.001   one thousandth
                0.01   one hundredth (1 in the hundredths place)
                0.1   one tenth (1 in the tenths place)
                
                1   one (1 in the ones or units place)
               10   ten (1 in the tens place)
              100   one hundred  (1 in the hundreds place)
              
            1,000   one thousand (1 in the thousands place)
           10,000   ten thousand
          100,000   one hundred thousand
          
        1,000,000   one million
       10,000,000   ten million
      100,000,000   one hundred million
      
    1,000,000,000   one billion
   10,000,000,000   ten billion
  100,000,000,000   one hundred billion
  
1,000,000,000,000   one trillion...

For names of larger numbers, see:

How Many? A Dictionary of Units of Measurement - Russ Rowlett

Large Numbers - Robert Munafo

And for the words with which we write numbers of all sizes, see:

Number Words Index: Numbers and Associated English Language Words, Phrases, Prefixes, Suffixes, and Symbols - Intergalactic Power & Light