1. Front End
&
Rounding
Gwendolyn Best
Suffolk Public Schools

2. Estimation
The next few slides
will help you
test your
estimation skills.

3. Can I buy three for $100?
45

4. Can I buy three for $100?
$23

5. Can I buy 5 for $50?
The basketball would have
to cost ______ or less for
me to purchase five of
them for $50.

6. Can I buy three for $20?
$
4.95

7. Rounding
to the highest
Place Value g hest
its hi
ber to ome
h num lue. S
d eac ce va ten-
Roun le pla ed to eds,
ib round hundr
poss rs will be ands,
numbe ds, thous
tho usan
or t ens.

8. 1 + 26 + 1,427 + 216
375 Hundreds
26 Tens
1,427 Thousands
216 Hundreds

9. Round to the highest place.
375 Hundreds 400
26 Tens 30
1,427 Thousands 1,000
216 Hundreds 200

10. After you round, add the numbers!
400
30
1000
+ 200
1630

11. 8857 8857
9000
4758 5000
4758
7045 7000
7045
+ 2110 + + 2110
2000

12. 9000 • Between 11,000 and 15,000
5000 • Between 16,000 and 20,000
7000 • Between 20,000 and 25,000
+2000
• Between 28,000 and 33,000

13. 247 247
200
6542 7000
6542
489 489
500
+ 92 + + 92
90

14. 200 • A little less than 7,000
7000
• A little less than 8,000
500
+ 90 • A little more than 8,000
• A little more than 10,000

15. 5028
5000
5028
6732
7000
6732
1285
1000
1285
+ 835 ++ 835
800

16. Front End Estimation

17. FRONT END
The name of this strategy gives you a clue
about how it is used.
The word FRONT should remind you that
you are only concerned with the front
portion of the number.
Many people think this strategy is easier
than rounding to the highest place value.

18. Draw a line through your list of numbers so
that you have at least one digit from each
addend in front of (before) the line.
ll
ge a
4,329 Chan ers
4,32 0 b
num he line
748 a fter t s.
o
74 0 t o zer
2,398
2,39 0 ll num he
bers
A
+ 28 be
t
fore the
+ 20 lin e s ta
y
.
s ame

19. 1 + 26 + 1,427 + 216
375 37 0
26 20
1,427 1,42 0
216 21 0

20. 8857 8857
8000
4758 4000
4758
7045 7000
7045
+ 2110 + + 2110
2000

21. 8857
8000
8857
4000
4758
4758
7000
7045
7045
+ + 2110
2000
+ 2110
Draw the line after the
first number
In each addend.

22. 8000 • Between 11,000 and 15,000
4000 • Between 16,000 and 20,000
7000 • Between 20,000 and 25,000
+2000
• Between 28,000 and 33,000

23. 247 247
240
6542 6540
6542
489 489
480
+ 92 + + 92
90

24. Estimate to find the best answer.
240 • A little more than 7,000
6540
• A little more than 8,000
480
+ 90 • A little less than 9,000
7350
• A little less than 10,000

25. 5028
5000
5028
6732
6700
6732
1285
1200
1285
+ 835 ++ 835
800

26. Estimate and choose the most
reasonable answer.
Between 11,000 and 15,000
5000
6700 Between 16,000 and 20,000
1200 Between 20,000 and 25,000
+ 800
Between 28,000 and 33,000
13700

27. 3,876 4,000 3,000
5,814 6,000 5,000
3,176 3,000 3,000
+ 7,895 + 8,000 + 7,000

28. 9,876 9,000 10,000
8,514 8,000 9,000
6,092 6,000 6,000
+ 3,895 + 3,000 + 4,000