Rounding Numbers to the Nearest Hundred by Mrs. Zagrodny

When you find the hundred that is closest to a number, you are rounding.

For example, 400 is the closest ten to 360. So, 360 to the nearest 100 is rounded to 400.

Again, let’s think about a number line like a roller coaster.

You might think about a number line that looks like this:

On this number line, what number would come half way between 100 and 200?

What number would come half way between 200 and 300?

What hundred would be next? What number would be half way between?

Can you guess about where 170 would be on this number line?

If the roller coaster stopped, what number would it roll to?

Can you guess about where 230 would be on this number line?

If the roller coaster stopped, what number would it roll to?

Can you guess about where 360 would be on this number line?

What would you round it to?

Can you guess about where 410 would be on this number line?

What would you round it to?

Can you guess about where 190 would be on this number line?

Can you guess about where 190 would be on this number line?

What would you round it to?

What about a number like 250? It’s right in the middle!

Our rule is to round to the next hundred

Tell a number that would round to

When you round to the nearest hundred, look in the tens place. If it has 1,2,3, or 4 round down. If it has 5, 6,7, 8, or 9 round up.

To round remember this rhyme, 5, 6, 7, 8, 9 GO UP all the time!!

Rounding numbers is so fun, We will do it 'till we're done. If a number's 1-4, Round it down right through the floor. If a number's 5-9, Round it up it is just fine. Round up, Round down, 1,2,3, , 3-4

Now it’s your turn! You can get some help from the number line.

What hundred is closest to 560? Put your bean on the closest hundred.

What hundred is closest to 790? Put your bean on the closest hundred.

What hundred is closest to 830? Put your bean on the closest hundred.

What hundred is closest to 990? Put your bean on the closest hundred.

What hundred is closest to 650? Put your bean on the closest hundred.

What hundred is closest to 940? Put your bean on the closest hundred.

Are you roller coaster ready for an assignment?