Rounding Powerpoint
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Transcript Rounding Powerpoint
rd
3
Grade
Rounding
By Monica Yuskaitis
California Standard Addressed
Number
Sense
Third
Grade
1.4 Round off numbers to 10,000
to the nearest ten, hundred, and
thousand.
Copyright © 2000 by Monica Yuskaitis
Objectives
To
be able to round numbers to the
nearest ten
To be able to round numbers to the
nearest hundred
To be able to round numbers to the
nearest thousand
Copyright © 2000 by Monica Yuskaitis
Vocabulary
Round – to replace an exact number
by another that is close to it in value
and easier to use. For example, 52,
rounded to the nearest ten is 50.
Copyright © 2000 by Monica Yuskaitis
Use rounding
• When the question asks you
to estimate.
• When the question asks
“about how many”…?
• When an exact answer isn’t
possible.
• When an answer is difficult
to obtain.
Copyright © 2000 by Monica Yuskaitis
Memorize this Poem
Find your number.
Look right next door.
4 or less just ignore.
5 or more, add 1 more.
Copyright © 2000 by Monica Yuskaitis
Round this number to the nearest
ten.
Find your number.
47
Circle the number in the tens
place.
Copyright © 2000 by Monica Yuskaitis
Round this number to the nearest
ten.
Look right next door.
47
Draw an arrow to the right of the
number.
Copyright © 2000 by Monica Yuskaitis
Round this number to the nearest
ten.
4 or less, just ignore.
47
7 is larger than 4 so go to the
next line of the poem.
Copyright © 2000 by Monica Yuskaitis
Round this number to the nearest
ten.
5 or more, add 1 more.
+1
47
Add 1 to the 4.
Copyright © 2000 by Monica Yuskaitis
Round this number to the nearest
ten.
5 or more, add 1 more.
50
After adding 1 to the 4, all the numbers
to the right of the 5 become 0’s.
Copyright © 2000 by Monica Yuskaitis
The Answer
4 7 rounded to the
nearest tens place is
50
40
47
50
Note 47 is closer to 50 on the number line.
Copyright © 2000 by Monica Yuskaitis
Round this number to the nearest
hundred.
Find your number.
986
Circle the number in the hundreds
place.
Copyright © 2000 by Monica Yuskaitis
Round this number to the nearest
hundred.
Look right next door.
986
Draw an arrow to the right of the
number.
Copyright © 2000 by Monica Yuskaitis
Round this number to the nearest
hundred.
4 or less, just ignore.
986
8 is larger than 4 so go to the
next line of the poem.
Copyright © 2000 by Monica Yuskaitis
Round this number to the nearest
hundred.
5 or more, add 1 more.
+1
986
Add 1 to the 9.
Copyright © 2000 by Monica Yuskaitis
Round this number to the nearest
hundred.
5 or more, add 1 more.
1, 0 0 0
After adding 1 to the 9, all the numbers
to the right of the 10 become 0’s.
Copyright © 2000 by Monica Yuskaitis
The Answer
986 rounded to the
nearest hundreds place is
900
1, 0 0 0
986 1,000
Note 986 is closer to 1,000 on the number
line.
Copyright © 2000 by Monica Yuskaitis
Round this number to the nearest
thousand.
Find your number.
3 5, 3 2 7
Circle the number in the thousands
place.
Copyright © 2000 by Monica Yuskaitis
Round this number to the nearest
thousand.
Look right next door.
3 5, 3 2 7
Draw an arrow to the right of the
number.
Copyright © 2000 by Monica Yuskaitis
Round this number to the nearest
thousand.
4 or less, just ignore.
3 5, 3 2 7
Since 3 is less than 4 we do not change
the 5.
Copyright © 2000 by Monica Yuskaitis
Round this number to the nearest
thousand.
4 or less, just ignore.
3 5, 0 0 0
Change the numbers to left of 5 to 0’s.
Copyright © 2000 by Monica Yuskaitis
The Answer
35,327 rounded to the
nearest thousand is
3 5, 0 0 0
35,000
35,327
36,000
Note 35,327 is closer to 35,000 on the
number line than to 36,000.
Copyright © 2000 by Monica Yuskaitis
Round these numbers to the
nearest ten.
139
140
45
50
282
280
97
100
Copyright © 2000 by Monica Yuskaitis
Round these numbers to the
nearest hundred.
2, 1 3 9
2, 1 0 0
1 9, 7 4 5
1 9, 7 0 0
282
300
3, 1 9 7
3, 2 0 0
Copyright © 2000 by Monica Yuskaitis
Round these numbers to the
nearest thousand.
2, 8 3 9
3, 0 0 0
1 9, 4 4 5
1 9, 0 0 0
8, 9 8 2
9, 0 0 0
4 3,1 9 7
4 3, 0 0 0
Copyright © 2000 by Monica Yuskaitis
Credits
Illustrations from:
Clipart
from ClickArt 125,000 Deluxe
Image Pak, T/Maker Co., Broderbund
Software, Inc.
Copyright © 2000 by Monica Yuskaitis