1. Lesson 8: Rounding Numbers
October

2. Let’s Get Set!!

3. Vocabulary
Round = to approximate the value of a number by finding the nearest ten, hundred, or other place value
To Estimate = to give an approximate number
An Estimate = a close guess made using mathematical thinking

4. Let’s review Place Value
thousands
hundreds
tens
ones

5. Let’s use a hundreds chart!!!
Watch Me!!!
Ally records the time she spends doing homework. She rounds each time to the nearest ten minutes. Ally spends 37 minutes on her homework. How does she record this time?
Let’s use a hundreds chart!!!

6. Remember This

7. Round 943 to the nearest ten.
Partner Talk
Round 943 to the nearest ten.
943 is between what two tens? __________________
What number is halfway between these two tens? ________
Is 943 less than or greater than the halfway number? _________
Do you round 943 up or down? _______
What is 943 rounded to the nearest ten? ________

8. Do You Understand? Let’s Check!!!
True or False?????
rounded to the nearest ten is 80
135 rounded to the nearest ten is 140
83 rounded to the nearest hundred is 100
382 rounded to the nearest ten is 400
45 rounded to the nearest ten is 50
274 rounded to the nearest ten is 270

9. Let’s Practice

10. Independent Time
Round to the nearest ten. What is a number less than 180 that rounds to 180?
What is a number greater than 180 that rounds to 180?

11. Let’s Wrap it Up!

12. Show Me What You Learned!
Which numbers are rounded correctly?
Choose ALL of the correct answers.
444 rounded to the nearest ten is 440.
361 rounded to the nearest hundred is 400.
547 rounded to the nearest hundred is 500.
255 rounded to the nearest ten is 250.
625 rounded to the nearest hundred is 630.