Let's Learn: Estimation | Mathematics (Maths Mela) Class 5 - New NCERT PDF Download

 Page 1


ROUNDING makes numbers easy to use in calculations
but is less accurate.
4 or less rounds DOWN 5 or more rounds UP
Two lollipops
Grandma has given you $5 to spend on treats at the supermarket.
You want to buy the following:
$1.80 each A packet of chips
$1.10 each
E S T I M A T I ON
ESTIMATION
U S I N G
USING
What is estimation?
An estimation is a rough calculation of something. For example:
If the weather for tomorrow is predicted to be 19 degrees,
we could say it will be roughly 20 degrees.
How can we estimate?
A great tool to help us estimate is ROUNDING.
TIPS FOR ROUNDING
We usually round by using the following rules:
Page 2


ROUNDING makes numbers easy to use in calculations
but is less accurate.
4 or less rounds DOWN 5 or more rounds UP
Two lollipops
Grandma has given you $5 to spend on treats at the supermarket.
You want to buy the following:
$1.80 each A packet of chips
$1.10 each
E S T I M A T I ON
ESTIMATION
U S I N G
USING
What is estimation?
An estimation is a rough calculation of something. For example:
If the weather for tomorrow is predicted to be 19 degrees,
we could say it will be roughly 20 degrees.
How can we estimate?
A great tool to help us estimate is ROUNDING.
TIPS FOR ROUNDING
We usually round by using the following rules:
Two lollipops
Grandma has given you $5 to spend on treats at the
supermarket. You want to buy the following:
$1.80 each A packet of chips
$1.10 each
Page 3


ROUNDING makes numbers easy to use in calculations
but is less accurate.
4 or less rounds DOWN 5 or more rounds UP
Two lollipops
Grandma has given you $5 to spend on treats at the supermarket.
You want to buy the following:
$1.80 each A packet of chips
$1.10 each
E S T I M A T I ON
ESTIMATION
U S I N G
USING
What is estimation?
An estimation is a rough calculation of something. For example:
If the weather for tomorrow is predicted to be 19 degrees,
we could say it will be roughly 20 degrees.
How can we estimate?
A great tool to help us estimate is ROUNDING.
TIPS FOR ROUNDING
We usually round by using the following rules:
Two lollipops
Grandma has given you $5 to spend on treats at the
supermarket. You want to buy the following:
$1.80 each A packet of chips
$1.10 each
$ 1 . 8 0
$ 1 . 0 0
$ 1 . 0 0
+
$ 3 . 8 0
One packet of chips
Two lollipops
Page 4


ROUNDING makes numbers easy to use in calculations
but is less accurate.
4 or less rounds DOWN 5 or more rounds UP
Two lollipops
Grandma has given you $5 to spend on treats at the supermarket.
You want to buy the following:
$1.80 each A packet of chips
$1.10 each
E S T I M A T I ON
ESTIMATION
U S I N G
USING
What is estimation?
An estimation is a rough calculation of something. For example:
If the weather for tomorrow is predicted to be 19 degrees,
we could say it will be roughly 20 degrees.
How can we estimate?
A great tool to help us estimate is ROUNDING.
TIPS FOR ROUNDING
We usually round by using the following rules:
Two lollipops
Grandma has given you $5 to spend on treats at the
supermarket. You want to buy the following:
$1.80 each A packet of chips
$1.10 each
$ 1 . 8 0
$ 1 . 0 0
$ 1 . 0 0
+
$ 3 . 8 0
One packet of chips
Two lollipops
Let's estimate TO CHECK
$1.80 is closest to $2.00 $1.10 is closest to $1.00
 0.8 is greater than
0.5 so we round up!
1.10 is less than 1.50
so we round down!
Page 5


ROUNDING makes numbers easy to use in calculations
but is less accurate.
4 or less rounds DOWN 5 or more rounds UP
Two lollipops
Grandma has given you $5 to spend on treats at the supermarket.
You want to buy the following:
$1.80 each A packet of chips
$1.10 each
E S T I M A T I ON
ESTIMATION
U S I N G
USING
What is estimation?
An estimation is a rough calculation of something. For example:
If the weather for tomorrow is predicted to be 19 degrees,
we could say it will be roughly 20 degrees.
How can we estimate?
A great tool to help us estimate is ROUNDING.
TIPS FOR ROUNDING
We usually round by using the following rules:
Two lollipops
Grandma has given you $5 to spend on treats at the
supermarket. You want to buy the following:
$1.80 each A packet of chips
$1.10 each
$ 1 . 8 0
$ 1 . 0 0
$ 1 . 0 0
+
$ 3 . 8 0
One packet of chips
Two lollipops
Let's estimate TO CHECK
$1.80 is closest to $2.00 $1.10 is closest to $1.00
 0.8 is greater than
0.5 so we round up!
1.10 is less than 1.50
so we round down!
One packet of chips = $2.00
Two lollipops = 2 x $1.00 = $2.00
$2.00 + $2.00 = $4.00 total