LO: To be able to round numbers Mrs Vivien Criddle Westfield

LO: To be able to round numbers Mrs Vivien Criddle Westfield Middle School

What is rounding? Sometimes we want to add numbers in our head but the numbers are a bit tricky. We can estimate (take a good guess) the answer It is easier if we use numbers that are in 10s Rounding means we find the nearest 10

Up or Down Does the number end in 1, 2, 3, 4 Round down Does the number end in 5, 6, 7, 8, 9 Round up

Lets look at a number line Where do these numbers go? 64 21 39 83

Let’s take a closer look 21 Is 21 closer to 20 or 30? Does it end in 1, 2, 3 or 4?

Round down!

Another close look 39 Is 39 closer to 30 or 40? Does it end in 5, 6, 7, 8 or 9?

Round up!

Another close look 64 Is 64 closer to 60 or 70? Does it end in 1, 2, 3 or 4?

Round down!

Another close look 83 Is 83 closer to 80 or 90? Does it end in 1, 2, 3 or 4?

Round down!

Your turn Use your whiteboard Draw an arrow on it Show me Round up Round down

32

Round down!

97

Round up!

5

Round up!

71

Round down!