Mu ltiplication/Division Puzzles
puzzlesmentally.Fillin the blankboxes.
Solvethe multiplication/division
Examples:
*rl
300
2
600
3
t.
xrl
qoo
70
*rl
80
50
+,ooo
4
320
200
6.OOO
8
2,000
2.
400
*rl
8
80
9
600
3.
6 r l
I
4.
4
5
2,400
6.
80
*rl
30
=
o
o
o
o
*rl
4,000
36,000
2,700
20
56,000
I
7
3,500
7,000
5.
400
600
*rl
7
50
6+O
10,000
Makeup and solvesomepuzzlesof yourown.
7.
*, /
*rl
/[
o)
=
o
O
9.
It.
: 0.56+ 0,92
1 9 . 1 1- 1 0 . 9 4:
to.
: 2.86- 1.73
12.
: 0.52 + 0.25
139
Extended Multiplication Facts
Solvementally.
1 . 6 * 7 :
2 , 9 * 3 :
6x70:
9*30:
60*7=
90x3:
60*70:
90x30:
600x7:
900x3:
60x700:
90x300:
4 x 8 :
: 15
4 . 5 *
4x80=
30 x.
: 150
40x3:
30x
: 1,500
40xgg:
x 50: 150
400x6:
* 500 : 1,500
40xggg:
*9:54
5.
: 15,000
30x
:40
6 . 8 *
x90:540
8 x
* 90 : 5,400
80x
: 4,000
: 4,000
o
: 540
*50:400
6 x
: 5,400
*5:400
6 x
: 54,000
60x
5
x 500 : 400,000
@
€
@
o
c
o
: 6.3 + 8.7
9.
140
: 9.74- 5.48
8 . 7 . 3 6+ 2 . 1 4 :
to.
: 4.6 - 2.8
c)
6
€
r
Name
Estimating Sums
For all problems,writea numbermodelto estimatethe sum.
a lf the estimateis greaterthanor equalto 1,500,findthe exactsum.
t
lf the estimateis lessthan 1,500,do not solvethe problem.
t. 867 + 734 =
7.
2. 374 + 962 + 488 :
Numbermodel:
Numbermodel:
3 8 2+ 7 4 4 :
581+648+366:
Numbermodel:
Numbermodel:
3 1 8+ 2 9 5+ 4 9 3=
845 + 702:
Numbermodel:
Numbermodel:
694 + 210 + 386 :
8
Numbermodel:
132 + 692 + 803 :
Numbermodel:
o
e. 756 + 381 + 201 :
10. 575 + 832:
(o
@
Numbermodel:
Num bermodel:
€
@
o
c
o
€
I
1t. 6 0 * 8 0 :
12.
30x70=
13. 5 0 x 9 0 0 :
14.
40*800:
144
Name
Estimating Products
Estimate
whetherthe answerwillbe in the tens,hundreds,
thousands,
or more.Writea numbermodelto showhowyou estimated.
Thencircle
the boxthat showsyourestimate.
l. A koalasleepsan averageol22hours eachday.Abouthow manyhours
doesa koalasleepin a year?
Numbermodel:
10s
100s
1 ,0 0 0 s
10.000s 100.000s 1,000,000s
A prairievole (a mouselikerodent)has an averageof 9 babiesper litter.
lf it has 17 littersin a season,abouthow manybabiesare produced?
Numbermodel:
10s
100s
1 ,0 0 0 s
10,000s 100,000s1,000,000s
Golferslose,on average,about5 golfballsper roundof play.Abouthow manygolf
ballswill an averagegolferloseplayingone roundeveryday for one year?
Numbermodel:
10s
100s
1 ,0 0 0 s
10,000s 100,000s1,000,000s
In the nexthour,the peoplein Francewillsave12,000treesby recycling
paper.Abouthow manytreeswilltheysavein two days?
o
N u m b em
r odel:
J
10s
100s
1 ,0 0 0 s
10,000s 100.000s 1,000,000s
@
€
@
c
o
G)
9)
5. Howmanydigitscanthe productof two 2-digitnumbershave?
Giveexamples
to supportyouranswer.
6.60x7:
148
2.4*80:
8.
€
I
:200*9
Name
Multiplication
Multiplyusingthe partial-product
method.Showyourworkin the gridbelow.
2. I * 275:
r.56*7=
Mayagoesto schoolfor 7 hourseachday. lf she doesnot missany of the
181schooldays,how manyhourswill Mayaspendin schoolthisyear?
a. Estimatewhetherthe answerwill be in the tens,hundreds,thousands,or more.Write
a numbermodelto showhowyou estimated.Circlethe box that showsyourestimate.
Numbermodel:
10s
100s
1,000s
b. Exactanswer:
10.000s 100,000s 1,000,000s
hours
The averageeye blinksonceevery5 seconds.ls that morethanor lessthan a hundred
thousandtimesperday? Explainyouranswer.
l
i
; "-- - **-,
i
i
t
i
* . _ l * - r i
I
3
(B
i
l
l
i
t
i
l
(t
l
i
l
]
r
i
l
l
l
l
l
l
i
!
i
:
t
t
l
t
l
i
:
i
l
i
i
I
i
i
r
l
i
:
l
i
d
=
o
o
i
o
o
c
;
O
: 495 + 7,389
8. 3,007 - 1,749 :
1
9
5,638+ 5,798:
: 8,561 - 3,872
151
More Multiplication
Multiplyusingthe partial-products
algorithm.Showyourwork.
2. 56 x 30:
f. 582*7:
:27 * 18
3. 42 * 59:
:46*71
6. 340 * 50:
:241 x 31
:2 8 3 + 5 .4 3 9
t f . 5 , 5 8 3- 4 , 6 6 7 :
154
:769x49
10.
12.
6,473+ 4,278:
:9,141 - 6,372
Lattice Multiplication
Use the latticemethodto find the followingproducts.
t.5*46:
2.8x67:
4. 4 * 329:
w
li
li
li
I
s.25x31:
6. 49 x 52:
I
=
o
o
c
7. Usethe latticemethodand the partial-products
methodto findthe product.
84*78:
3
@
;
8.
: 33.67+ 5.9
t o . 7 1 .4 4- 3 7 .6 7:
e. 68.4+ 5.82:
ll
: 101.06- 29.91
157
Name
Place-Value Puzzle
chart.
Usethe cluesbelowto fill in the place-value
Billions
1008 1 0 8 1 B
Millions
t
1 00M 1 0 M 1 M
Thousands
,
t00Tr1oTh l T h
Ones
100 1 0
1
I
t . Find2 of 24. Subtract4. Writethe resultin the hundredsplace.
place.
Find] of 30. Dividethe resultby 3. Writethe answerin the ten-thousands
place.
Find30 + 10.Doublethe result.Writeit in the one-millions
4.
Divide12 by 4. Writethe answerin the onesplace.
5.
Find9 * 8. Reversethe digitsin the result.Divideby 3.
place.
Writethe answerin the hundred-thousands
place.
Double8. Dividethe resultby 4. Writethe answerin the one-thousands
7.
place,writethe evennumbergreaterthan0
In the one-billions
that has not beenusedyet.
place.
Writethe answerto 5 -: 5 in the hundred-millions
ln the tens place,writethe odd numberthat has not beenusedyet.
10.
Findthe sum of all the digitsin the chartso far.
place.
Dividethe resultby 5, and writeit in the ten-billions
o
11.
Write0 in the emptycolumnwhoseplacevalueis lessthanbillions.
c
12.
Writethe numberin words.Forexample,17,450,206
couldbe writtenas
"17 million,450 thousand,
206."
I
3
6
=
=
@
E
o
oO
13. 74x 5:
15.
14.
:92 * 18
:396*8
16.56*47:
163
Many Names for Powers of 1O
Beloware differentnamesfor powersof 10.Writethe namesin the appropriate
name-collection
boxes.circle the namesthat do not fit in any of the boxes.
1 ,0 0 0 ,0 0 0
100
1 0[1 0 ,0 0 0 s]
10,000
1,000
10
10 [100,00 0s ]
106
10 [1,000s]
103
10x10x10x10
one thousand
10s
10*10*10x10x10
1 0[ 1 0 s ]
1 0* 1 0
ten
101
10 [tenths]
100
1
:495 * 6
:97x53
167
Time
Name
Rounding
L Roundthe seatingcapacitiesin the tablebelowto the nearestthousand.
Women's National Basketball Association
Seating CapacitY of Home Courts
Team
SeatingCapacity
CharlotteSting
24,042
ClevelandRockers
20,562
DetroitShock
22,076
NewYorkLiberty
19,763
PhoenixMercury
19,023
Monarchs
Sacramento
17,317
SanAntonioStars
18,500
SeattleStorm
17,072
Roundedto the
Nearest1,000
z. Lookat your roundednumbers.Whichstadiumshaveaboutthe samecapacity?
g. Roundthe population
figuresin the tablebelowto the nearestmillion.
U.5. population by official census from 1940 to 2ooo
I
3
G
Year
Population
1940
132,164,569
1960
179,323,175
1980
226,542,203
2000
291,421,906
Roundedto the
NearestMillion
(5
a
o
f
c
o
(9
!
o
o
o
Sourcefor both tables:The WortdAfmanacand Book of Facts2004
4.
:692x0
:39*21
6. 44 * 7g:
169
Name
Comparing Data
Thistableshowsthe number
of poundsof fruitproducedby the
top 10 fruit-producing
countriesin
2001.Readeachof thesenumbers
to a friendor a familymember.
Country
Poundsof Fruit
Brazil
77,269,294,000
China
167,046,420,000
France
t. Whichcountryproducedthe
mostfruit?
Whichcountryproducedthe
leastfruit?
26,823,740,O00
lndia
118,036,194,000
lran
28,599,912,000
Italy
44,410,539,000
Mexico
34,549,912,000
Philippines
27,028,556,000
Spain
36,260,392,000
UnitedStates
73,149,599,000
s. For eachpair,circlethe countrythat producedmorefruit.
a. India
Mexico
b. United States
c. Brazil
Philippines
d. Spain
lran
ltaly
+. Whichtwo countriestogetherproducedaboutas muchfruitas India?
o
=
@
€
(o
Estimate
the sum.Writea numbermodel.
f
o
o
5. 687 + 935
o
0)
e . 2 , 4 0 9+ 1 , 1 9 6+ 1 , 3 2 7
7 . 1 1 , 8 9 9+ 3 5,2 0 1
172
€
I