Rounding Decimals
Use place value understanding to
round decimals to any place. Use
place value understanding to round
decimals to any place.
5.NBT.4
Where do we see Decimals being used?
Look behind the photos to find out!
Decimals are used in swimming
times to get the most accurate
results. A typical swim time
measures minutes, seconds, and
fractions of a second.
Example: 1:52.28
Scientists use decimals to
show more accurate
measurements in their
data. This helps them to
notice small changes in
the data.
Basketball
shooting
percentages use
decimals to show
how often players
make shots.
Example: 0.421
You use decimals
when talking about
money. The change is
expressed after the
decimal point as in
$1.62.
Decimals on the Number Line
2.1 2.2 2.3 2.4 2.5 2.6 2.7 2.8 2.9
2
3
What does each line represent on this number line between
the whole numbers of 2 and 3?
Label the number line.
Decimals on the Number Line
4.33
4.31
4.3
4.32
4.34
4.37
4.35
4.36
4.39
4.38
4.4
What does each line represent on this number line between
the decimal numbers of 4.3 and 4.4?
Label the number line.
Where would you place 4.4 on this
number line?
4
0
5
A B C D
10
Rounding 2.728 to the nearest whole
number
2.5
2
3
2.5 is in the middle of 2 and 3.
On which side of the hill would 2.728 be?
Is 2.728 closer to 2 or to 3?
Rounding 2.728 to the nearest whole
number
2.728
2
3
Is 2.728 closer to 2 or to 3?
Rounding 2.728 to the nearest tenth
2.75
2.7
2.8
2.75 is in the middle of 2.7 and 2.8
On which side of the hill would 2.728 be?
Is 2.728 closer to 2.7 or to 2.8?
Rounding 2.728 to the nearest tenth
2.728
2.7
2.8
Is 2.728 closer to 2.7 or to 2.8?
Rounding 2.728 to the nearest
hundredth
2.725
2.72
2.73
2.725 is in the middle of 2.72 and 2.73
On which side of the hill would 2.728 be?
Is 2.728 closer to 2 or to 3?
Rounding 2.728 to the nearest
hundredth
2.728
2.72
2.73
Is 2.728 closer to 2.72 or to 2.73?
Rounding 6.293 to the nearest whole
number
6.5
6
.
7
6.5 is in the middle of 6 and 7
Which side of the hill would 6.293 be on?
Is 6.293 closer to 6 or 7?
Rounding 6.293 to the nearest whole
number
6.293
6
7
.
Is 6.293 closer to 6 or to 7?
Rounding 6.293 to the nearest tenth
6.25
6.2
6.3
.
6.25 is in the middle of 6.2 and 6.3
Which side of the hill would 6.293 be on?
Is 6.293 closer to 6.2 or 6.3?
Rounding 6.293 to the nearest tenth
6.293
6.2
.
Is 6.293 closer to 6.2 or to 6.3?
6.3
Rounding 6.293 to the nearest
hundredth
6.295
6.29
.
6.3
6.295 is in the middle of 6.29 and 6.3
Which side of the hill would 6.293 be on?
Is 6.293 closer to 6.29 or 6.3?
Rounding 6.293 to the nearest tenth
6.293
6.29
Is 6.293 closer to 6.2 or to 6.3?
.
6.3
Round each number to the nearest
hundredth
a. 4.025
b. 6.088
c. 3.202
d. 4.116
e. 2.066
f. 1.908
David swam 2.549 miles. He rounded his
distance to 3 miles. His coach rounded his
distance to 2.5 miles.
Both are right!
Explain how this could be true.
Use number lines and words to explain
your reasoning.