1. Continue the number pattern below. Explain the pattern you found.
Challenge of the Day
Continue the number pattern below. Explain the pattern you found.
3, 6, 10, 15, ___, ___
21, 28;
One possible pattern is to increase the difference between consecutive terms by one more than the difference between preceding consecutive terms.

2. Visit the Brain Pop Site below
Username = wwpcms
Password = middle

3. Round to specific place values and estimate with whole numbers.

4. Vocabulary
Estimates - are close to the exact answer but are usually easier and faster to find.
Compatible numbers - When estimating, these numbers are close to the numbers in the problem, and can help you do math mentally.

5. Underestimate - An estimate that is less than the exact answer.
Overestimate - An estimate that is greater than the exact answer.

6. Rounding Rules – Whole Numbers
Underline the place to which you are rounding;
Look to the place value IMMEDIATELY to the right of the underlined number (it helps to circle this number). The circled number is “The Teller”. The “TELLER” tells you which rounding rule to apply.
Rule 1 Is it less than 5?
Leave the underlined number alone
Rule 2 Is it 5 or greater?
Round underlined number up to the
next whole number (you are really
adding 1 to the underlined number).

7. Fill in the digits to the left of the rounded place value, if there are any.
Add zeroes to replace any digits to the right of the rounded place value. Stop at the INVISIBLE decimal point.

8. Tens place Hundreds place 4 9, 4 5 3 4 9,4 5 3 4 9, 4 5 0 4 9, 5 0 0
Classroom Example
Round 49,453 to the following place values:
Tens place
Hundreds place
4 9, 4 5 3
4 9,4 5 3
4 9, 4 5 0
4 9, 5 0 0
Thousands place
Ten thousands place
4 9, 4 5 3
4 9, 4 5 3
4 9, 0 0 0
5 0, 0 0 0

9. If that digit is 5 or greater, add one to the underlined number.
When rounding, look at the digit to the right of the place to which you are rounding.
If that digit is 5 or greater, add one to
the underlined number.
If that digit is less than 5, leave the
underlined number alone.
Remember!

10. 1A: Estimating a Sum or Difference by Rounding
Estimate the sum by rounding to the place value indicated.
12, ,167; ten thousands
Round 12,345
10,000
Round 62,167
+ 60,000
__________
70,000
The sum is about () 70,000.

11. 1B: Estimating a Sum or Difference by Rounding
Estimate the difference by rounding to the place value indicated.
4,983 – 2,447; thousands
Round 4,983
5,000
Round 2,447
– 2,000
3,000
The difference is about () 3,000.

12. Check It Out: Example 1A
Estimate the sum by rounding to the place value indicated.
13, ,139; ten thousands
Round 13,235
10,000
Round 41,139
+ 40,000
50,000
The sum is about () 50,000.

13. Check It Out: Example 1B
Estimate the difference by rounding to the place value indicated.
5,723 – 1,393; thousands
Round 5,723
6,000
Round 1,393
– 1,000
5,000
The difference is about () 5,000.

14. Estimating a Product by Rounding
Chelsea is planning the annual softball banquet for the 8 teams in the region. Each team has 18 members. Estimate how many plates she will need to buy if all the members attend.
Find the number of softball members.
Overestimate the number of softball members.
8 • 18
The actual number of softball members is less than 160.
8 • 20 = 160
Chelsea should buy about () 160 plates.

15. Example 2 Continued
Another method
Find the number of softball members.
Overestimate the number of teams.
8 (18) (18)
The actual number of softball members is less than 180.
10 (18) = 180
Chelsea should buy about () 180 plates.

16. Check It Out: Example 2
Ms. Oliver wants to buy the entire seventh-grade new pencils. There are 5 seventh-grade homeroom classes of 28 students. Estimate how many pencils Ms. Oliver needs to buy for all of the students.
Find the number of students in the seventh grade.
Overestimate the number of students.
5 (28) 5 (30)
The actual number of students is less than 150.
5 (30) = 150
Ms. Oliver should buy about () 150 pencils.

17. Example 3: Estimating a Quotient Using Compatible Numbers
Mr. Dehmel will drive 243 miles to the fair at 65 mi/h. About how long will his trip take?
Round to the same place value if you are rounding both numbers
243 ÷ 65
240 and 60 are compatible numbers.
240 ÷ 60
= 4
Because he underestimated the speed, the actual time will be less than 4 hours.
The trip will take about () 4 hours.

18. Lesson Quizzes
Lesson Quiz
Multiple Choice Lesson Quiz

19. Lesson Quiz
Estimate each sum or difference by rounding to the place value indicated.
1. 7, ,527; thousands
2. 47, ,925; ten thousands
3. 8,254 – 5,703; thousands
4. 66,845 – 24,782; ten thousands
5. One quart of paint covers an area of 100 square feet. How many quarts are needed to paint a wall 8
feet tall and 19 feet wide?
about () 11,000
about() 70,000
about () 2,000
about () 50,000
about () 2

20. Multiple Choice Lesson Quiz
1. Estimate by rounding to the indicated place value , ,428; thousands
A. about () 10,000
B. about () 11,000
C. about () 12,000
D. about () 13,000

21. Multiple Choice Lesson Quiz
2. Estimate by rounding to the indicated place value. 52, ,725; ten thousands
A. about () 60,000
B. about () 70,000
C. about () 80,000
D. about () 90,000

22. Multiple Choice Lesson Quiz
3. Estimate by rounding to the indicated place value – 4860; thousands
A. about () 1,000
B. about () 2,000
C. about () 3,000
D. about () 4,000

23. Multiple Choice Lesson Quiz
4. Estimate by rounding to the indicated place value. 55,726 – 25,832; ten thousands
A. about () 50,000
B. about () 40,000
C. about () 30,000
D. about () 20,000

24. Multiple Choice Lesson Quiz
5. One gallon of floor polish is required to polish an area of 50 square feet. How many gallons are required to polish a floor 9 feet long and 11 feet wide?
A. about () 1 gallon
B. about () 2 gallons
C. about () 3 gallons
D. about () 4 gallons