Transcript Rounding to the Nearest Ten

Creator: Jamin Jones
Class CEP: 811
Date: October 29, 2012
Rounding whole
numbers and decimals
Objectives
You will be able to…
1. Understand place value up to the tenths and
hundredths
2. Round numbers to the nearest tenth and
hundredth
Core standard:OBJ05CCMA07: Use place value
understanding to round decimals to any place. It
is the common core curriculum standard for 5th
grade students.
Road Map
Part One:
• Round numbers to the nearest tens
• Round numbers to the nearest hundreds
Part Two:
• Identify tenths place
• Identify hundredths place
Part Three:
• Round to the nearest tenths place
Key Vocabulary
Round -
To replace a number with a
number that tells about how
many.
About -
Around or close to.
Part 1
Why do we round?
1. When we round, we change a
number into another number that
it is close to.
2. Rounding numbers is a good
way to estimate about how
much you have.
Rounding rule
5 is in the middle of
0 and 10.
0
1
2
3
4
5
6
When rounding we have to decide if we are going to
round up or down. Placement on a the number line
can helps us see where to round.
7
8
9
10
Rounding rule
5 and above give it a shove.
0
1
2
3
4
5
6
7
8
9
10
Why do we round?
4 or below leave it
alone.
0
1
2
3
4
5
6
7
8
9
10
Rules
•
•
•
•
Look at the number before
4 and below leave it alone
5 and above give it a shove
Make everything after it a zero
Rounding to the Nearest Ten
26
Click on the number
in the tens place.
Great Job!!!
26
ones
tens
Try again.
Remember place
value order.
3 5
tens
ones
When rounding we look at
the number before the 10.
26
If it is 5 and above you give
the tens place a shove.
26
The 2 becomes a 3 and the 6
becomes a 0.
30
26
rounds to
30
Let’s try another
32
Click on the number in the tens place.
Great Job!!!
32
ones
tens
Try again.
Remember place
value order.
3 5
tens
ones
Let’s try another
32
Shove
The 2 is below 5.
Is it going to
shove the 3 or
leave it alone?
Leave
Great Job!!!
4 and below leave it alone
Try again.
Remember the
rule.
-5 and above give it a shove
-4 and below leave it alone
Let’s try another
30
The 3 stays the same and the 2
becomes a 0.
Another way
10
11
12
13
14
15
16
17
Picture the number on a number line and
look for the number it is closest to.
18
19
20
Another way
10
11
12
13
14
15
16
17
18
If you were to find 17 on a number line, would it be closer to
10 or 20?
10
20
19
20
Try again.
Remember the
rule.
17 is 7 away from 10, but
only 3 away from 20.
Great Job!!!
17 is only 3 away from 20.
Let’s Practice
Rounds to
38
30
or
40
53
50
or
60
16
10
or
20
44
40
or
50
Great Job!!!
38 rounds up to 40
Try again.
Remember the
rule.
If the ones place is:
-5 and above give the tens a shove
-4 and below leave the tens alone
Great Job!!!
53 rounds down to 50
Try again.
Remember the
rule.
If the ones place is:
-5 and above give the tens a shove
-4 and below leave the tens alone
Great Job!!!
16 rounds up to 20.
Try again.
Remember the
rule.
If the ones place is:
-5 and above give the tens a shove
-4 and below leave the tens alone
Great Job!!!
44 rounds down to 40.
Try again.
Remember the
rule.
If the ones place is:
-5 and above give the tens a shove
-4 and below leave the tens alone
Rounding to the Nearest
Hundred
134
Which number is in the
hundreds place?
Great Job!!!
134
hundreds
ones
tens
Try again.
Remember place
value.
1 5 3
hundreds
tens
ones
Rounding to the Nearest
Hundred
134
Use the first number to
the right of the
hundreds place to
decide if you round up
or down.
Rounding to the Nearest
Hundred
134
Shove
Is the 3 going to give the
hundreds column a
shove or leave it alone?
Leave
Try again.
Remember the
rule.
If the ones place is:
-5 and above give the tens a shove
-4 and below leave the tens alone
Great Job!!!
The one in 134 will be left alone.
Rounding to the Nearest
Hundred
100
134
rounds to
Everything else becomes a
zero.
100
Another way
100
110 120
130
140
150
160
170
Picture a number on the number line
between 2 hundreds. Which is it closest
to?
180 190 200
Another way
100
110 120
130
140
150
160
170
180 190 200
Would 131 round to 100 or 200?
100
200
Try again.
Remember the
rule.
If the ones place is:
-5 and above in the tens gives the hundreds
a shove
-4 and below in the tens leave the hundreds
alone
Great Job!!!
174 will round up to 200.
Let’s practice
Rounds to
174
100
223
200
or
300
562
500
or
600
or
200
Great Job!!!
174 will round up to 200.
Try again.
Remember the
rule.
If the ones place is:
-5 and above give the hundreds a shove
-4 and below leave the hundreds alone
Great Job!!!
223 will round down to 200.
Great Job!!!
562 will round up to 600.
Place Value – Part two
Hundreds Tens
Ones
Decimal
There is a pattern with place value that
starts from the ones and moves out.
Tenths
Hundredths
Place Value
Hundreds Tens
Ones
Decimal
Tenths
Hundredths
You start in the ones and move out.
Click on the arrow to follow the pattern.
Place Value
Hundreds Tens
Ones
Decimal
Tenths
Hundredths
Next comes the tenths on one
side.
Click on the arrow to follow the pattern.
Place Value
Hundreds Tens
Ones
Decimal
Tenths
Hundredths
And the tenths on the other side.
Click on the arrow to follow the pattern.
Place Value
Hundreds Tens
Ones
Decimal
Tenths
Hundredths
Next comes hundreds.
Click on the arrow to follow the pattern.
Place Value
Hundreds Tens
Ones
Decimal
Tenths
Hundredths
And then hundredths on the other side.
Place Value
Hundreds Tens
Ones
Decimal
Tenths
Hundredths
The major difference between the two sides is
that one side has a -th on the end and is a
smaller value.
Recognizing tenths
and hundreds
34.67
124.35
17.1
2.89
57.21
Click on the number below that
correctly answers the question
34.67
124.35
17.1
2.89
Find the
numbers with
a 6 in the
tenths.
57.21
Try again.
Remember the
place value
chart.
Hundreds Tens
Ones
Decimal
Tenths
Hundredths
Tens
Ones
Decimal
Tenths
Hundredths
3
4
.
6
7
Click on the number below that
correctly answers the question
34.67
124.35
17.1
2.89
Find the
numbers with
a 1 in the
tenths.
57.21
Try again.
Remember the
place value
chart.
Hundreds Tens
Ones
Decimal
Tenths
Hundredths
Tens
Ones
1
7
Decimal
.
Tenths
1
Click on the number below that
correctly answers the question
34.67
124.35
17.1
2.89
Find the
numbers with
a 1 in the
hundredths.
57.21
Try again.
Remember the
place value
chart.
Hundreds Tens
Ones
Decimal
Tenths
Hundredths
Tens
5
Ones
7
Decimal
.
Tenths
2
Hundredths
1
Click on the number below that
correctly answers the question
34.67
124.35
17.1
2.89
Find the
numbers with
a 5 in the
hundredths.
57.21
Try again.
Remember the
place value
chart.
Hundreds Tens
Ones
Decimal
Tenths
Hundredths
Great Job!!!
Hundreds
1
.
Tens
2
Ones
4
Decimal
.
Tenths
3
Hundredths
5
Click on the number below that
correctly answers the question
34.67
124.35
17.1
2.89
Find the
numbers with
a 8 in the
tenths.
57.21
Try again.
Remember the
place value
chart.
Hundreds Tens
Ones
Decimal
Tenths
Hundredths
Ones
Decimal
Tenths
Hundredths
2
.
8
9
Click on the number below that
correctly answers the question
34.67
124.35
17.1
2.89
Find the
numbers with
a 7 in the
hundredths.
57.21
Try again.
Remember the
place value
chart.
Hundreds Tens
Ones
Decimal
Tenths
Hundredths
Ones
Decimal
Tenths
Hundredths
2
.
8
9
Rounding Numbers to the
nearest tenth
We learned before that you round
numbers to estimate how much we
have.
We can round numbers to figure out
approximately how much we owe for a
bill.
Rounding Numbers to the
nearest tenth
When rounding to the nearest tenth it is
like rounding to the nearest 10 cents in
money.
If you don’t have exact change you can
round to find how much you will pay.
Rounding Numbers to the
nearest tenth
How do we do this?
Just like with rounding to the nearest
ten and hundred.
Rounding Numbers to the
nearest tenth
Step 1:
1.
2.
3.
4.
Look at the number to the right.
Is it a 5 and above or a 4 and below
Make the change to the correct place
Everything else after the number
being changed becomes a zero
Let’s Try
125.45
Which number is in
the tenths place?
Try again.
Remember the
place value
chart.
Hundreds Tens
Ones
Decimal
Tenths
Hundredths
Hundreds Tens
Ones
Decimal
Tenths
Hundredths
1
5
.
4
5
2
Will the 4 be
shoved up or
left the same?
125.45
Shove
Leave
Try again.
Remember the
rule.
-5 and above give it a shove
-4 and below leave it alone
Great Job!!!
4 and below leave it alone
125.50
4 is shoved up to 5 and
everything after it becomes a
zero.
Round to the
nearest tenth.
51.12
Which number is in the tenths?
Try again.
Remember the
rule.
-5 and above give it a shove
-4 and below leave it alone
Tens
Ones
Decimal
Tenths
Hundredths
5
1
.
1
2
Will the one be left
alone or give a
shove?
51.12
Shove
Leave
Try again.
Remember the
rule.
-5 and above give it a shove
-4 and below leave it alone
Great Job!!!
4 and below leave it alone
Click on the number below that correctly
rounds each number to the nearest tenth.
Rounds to
124.35
124.30
or
124.40
17.12
17.10
or
17.20
34.67
34.60
or
34.70
Try again.
Remember the
rule.
-5 and above give it a shove
-4 and below leave it alone
Great Job!!!
5 and above, give it a shove
Great Job!!!
4 and below leave it alone
Great Job!!!
5 and above give it a shove
You have completed
parts 1,2, and 3 of
rounding whole
numbers and decimals.
Credits
Created by: Jamin Jones
ClipArt: "©2012 Jupiterimages Corporation. All rights
reserved.“ and Microsoft office
Date :10/29/2012