07.01.21
Today we are going to look at rounding numbers to the nearest 100.
When rounding to the nearest 100 we need to follow a few simple rules.
Rules:
Key To Rounding (rule 3)!!
If the number in the column you are looking at is:
1,2,3 or 4 you round DOWN
5,6,7,8,9 you round UP
Lets have a look at this with a few examples.
Lets start with the number
213
Step 1
Find the nearest hundred below the number
So, what is the nearest 100 below 213?
Remember hundreds end in 00
The nearest hundred below 213 is 200
Step 2
Find the nearest hundred above the number
Now, what is the nearest 100 above 213?
The nearest hundred above 213 is 300
Step 3
Look at the Tens column to help us work whether we round above or below.
Finally we look at the tens column
213
What number is in the tens column?
1
Remember, if the number in the column you are looking at is:
1,2,3 or 4 you round DOWN
5,6,7,8,9 you round UP
So we would need to round to the lower hundred which will be 200.
Lets try another question
584
Step 1
Find the nearest hundred below the number
So, what is the nearest 100 below 584?
The nearest hundred below 213 is 500
Step 2
Find the nearest hundred above the number
Now, what is the nearest 100 above 584?
The nearest hundred above 213 is 600
Step 3
Look at the Tens column to help us work whether we round above or below.
Finally we look at the tens column
213
What number is in the tens column?
8
Remember, if the number in the column you are looking at is:
1,2,3 or 4 you round DOWN
5,6,7,8,9 you round UP
So we would need to round to the lower hundred which will be 600.
In your books have a go at rounding the following 6 numbers to the nearest 100.
Now go onto Purple mash and complete the 2do for maths.