02-NelsonMathGr6-Chap02 7/18/05 9:38 AM Page 50
CHAPTER 2
You will need
6
Goal
Reading and Writing
Decimal Thousandths
• thousandths grids
• a decimal place
value chart
Read, write, and model decimals.
Marc is writing a report on
the population of Canada.
He found this table showing the
number of people in each age
group for every 1000 people in
Canada In 2001.
Population by Age for Every 1000 People in 2001
Age group
Number for every 1000
Under 5 years
57
5–19 years
203
20–44 years
367
45–64 years
243
65 years or over
130
can a decimal be used to describe people who
? How
are 5 to 19 years old?
Marc’s Explanation
I write a fraction for the 5 to 19 years old.
203
1000
1
—
100
I use a grid made up of 10 columns,
each with 10 squares in it.
Each square is divided up into
10 rectangles that represent thousandths.
100
1000
1
10
10
1000
1
100
Each column is or .
Each square is or .
I colour 203 thousandths on a grid.
1
—
10
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02-NelsonMathGr6-Chap02 7/18/05 9:38 AM Page 51
Next, I write the number on a place value chart.
Tens match tenths and hundreds match hundredths on
opposite sides of the place value chart. Thousandths
must be the next place to match thousands.
Thousands
Hundreds
Tens
Ones
Tenths
Hundredths
Thousandths
2
0
3
In expanded form, 203 thousandths is
2 tenths 0 hundredths 3 thousandths.
The decimal for 5 to 19 year olds is 0.203.
Reflecting
1. How does the place value chart show that there are
10 thousandths in each hundredth (0.01)
and 100 thousandths in each tenth (0.1)?
2. When might you read 0.203 as 2 tenths 3 thousandths?
When might you read it as 203 thousandths?
Checking
3. Marc wants to represent each of the other age groups with
a decimal as well.
a) Write a fraction for each age group.
b) Colour a thousandths grid for each age group.
c) Write each number in expanded form.
d) Write a decimal for each age group.
4. In words, 0.34 can be written as 34 hundredths. Write each
decimal in words.
a) 0.120
b) 0.007
c) 0.305
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Practising
5. Which two age groups could be put together to cover
more than 0.500 of the thousandths grid, or more than
half of the total population?
6. The table shows the portion of Earth covered
by three oceans.
a) Write a fraction for each ocean.
b) Colour a thousandths grid to represent each fraction.
c) Write each number in expanded form.
d) Write a decimal for each ocean.
Portion of Earth Covered by Oceans
Pacific Ocean
three hundred fifty-two thousandths
Atlantic Ocean
two hundred nine thousandths
Arctic Ocean
twenty-eight thousandths
7. Each of these distances is in thousandths of a metre.
0.356 m
0.892 m
0.025 m
a) Write the words you would say to read each decimal.
b) Describe each distance in centimetres and millimetres.
8. Write a decimal in standard form to fit each description.
a) one thousandth greater than 2.548
b) one hundredth greater than 2.548
c) one tenth greater than 2.548
9. a) List two fractions that are equivalent to 0.500.
b) Rename 0.500 as a decimal hundredth and a decimal
tenth. How do you know they are equivalent decimals?
10. Why is 0.455 halfway between 0.45 and 0.46?
11. A thousandths grid is completely coloured in when three
different decimals are shown. One decimal is double one
of the others.
a) What could the three decimals be?
b) How do you know there are many answers to part a)?
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