Unit 1 - SD43 Teacher Sites

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Lesson 1: Place Value
12587654236841
Why is this number hard to read!?
4 538 902 761

For the number above, find and write the
digits for the following place values:
 ten thousands
 ones
 thousands
 ten millions
 billions
 hundred millions
Take these numbers and write
them with the correct spacing…
3412
 34125
 864312
 9004999
 60548902
 432157809

 3412
 34 125
 864 312
 9 004 999
 60 548 902
 432 157 809
Another student did this:
wrote 78939045672 as 789 390 456 72
 Is this right? Why or why not?
 What was this student thinking?
 Why did he/she make this mistake?

• How to avoid this mistake:
• Start at the right, draw lines in between every third digit.
• ex. 78939045672 
78|939|045|672 
78,939,045,672
45 3890 2761
What is the place value of the 5?
 Was it harder to read the place value in
the number this way?
 How is this spacing different from how
we usually write a number?
 We usually group place values by 3’s,
(ones, hundreds, thousands), so it’s
weird to see it grouped in 4’s.

In Japan, however…

their place value names look like this:
one
man
oku
chou
ten
ten man
ten oku
ten chou
hundred
hundred man
hundred oku
hundred chou
thousand
thousand man
thousand oku
thousand chou
man means ten thousand (10 000)
 what does oku mean?? How about chou???
 oku means 100 000, and chou means 1 000 000.
 This means their place values are grouped by 4’s!!

Comparing Values of Digits
What does it mean for a number to be so
many times another number?
 30 is 10 times 3, so 30 is ten times as big as
3.

How many times more is the first
3 worth than the second 3?
a)
b)
c)
d)
e)
f)
g)
h)
i)
j)
k)
l)
33
330
3300
33 000
334 507
3 398 412
303
3003
30 003
300 003
342 173
2 356 783 542
a) 10
b) 10
c) 10
d) 10
e) 10
f) 10
g) 100
h) 1000
i) 10 000
j) 100 000
k) 100 000
l) 100 000
How many times more is the 6
worth than the 3?
a)
b)
c)
d)
e)
f)
g)
h)
i)
j)
k)
l)
63
630
6300
63 000
634 507
6 398 412
603
6003
60 003
600 003
642 173
2 642 173 542
a)
b)
c)
d)
e)
f)
g)
h)
i)
j)
k)
l)
20
20
20
20
20
20
200
200
20 000
200 000
200 000
200 000
How many times more is the 3
worth than the 6?
a)
b)
c)
d)
e)
f)
g)
h)
i)
j)
k)
l)
36
360
3600
36 000
364 507
3 698 412
306
3006
30 006
300 006
342 176
2 342 176 542
a)
b)
c)
d)
e)
f)
g)
h)
i)
j)
k)
l)
5
5
5
5
5
5
50
500
5000
50 000
50 000
50 000
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