Advanced Model Drawing - Greenwood Primary School

Advanced Model
Drawing
A workshop for Parents by
Greenwood Primary
Workshop Outline
8.00 am to 8.10 am -
Introduction
8.10 am to 8.25 am -
Multiple Model
8.25 am to 8.50 am -
Hands-on Session 1
8.50 am to 9.05 am -
Difference Model
9.05 am to 9.25 am -
Hands-on Session 2
9.25 am to 9.30 am -
Q & A Session
Model Drawing Approach
In the process of grasping Mathematical concepts, children
understand best first through concrete manipulative,
followed by pictorial representations and lastly,
by attaining the ability to understand abstract concepts.
The Model Drawing approach provides a pictorial
representation that helps pupils better understand Mathematics
concepts.
Types of Model
• Part-Whole
• Comparison
• Multiple
• Difference
• Sharing
• Mixed
Multiple Model
Multiple Model Example 1
A bag cost 3 times as much as a wallet. If the wallet cost $36, how
much did the bag cost?
?
1 unit
B
= $36
3 units = $36 x 3
= $108
W
$36
The bag cost $108.
Multiple Model Example 2
A book cost 4 times as much as a pen. If the book cost $48, how
much did the pen cost?
$48
4 units = $48
B
1 unit
= $48 ÷ 4
= $12
P
?
The pen cost $12.
Multiple Model Example 3
A squash racket cost twice as much as a badminton racket.
They cost $360 altogether.
How much did the squash racket cost?
?
3 units = $360
1 unit
S
$360
B
= $360 ÷ 3
= $120
2 units = $120 x 2
= $240
The squash racket cost $240.
Multiple Model Example 4
A wardrobe cost 5 times as much as a study table.
The wardrobe cost $400 more than the study table.
How much did both items cost?
4 units = $400
1 unit
W
?
S
= $400 ÷ 4
= $100
6 units = $100 x 6
$400
= $600
Both items cost $600.
Try It Out!
Practice questions
Multiple Model Practice 1
Mrs. Loh paid $104 for a blouse and a skirt.
The blouse cost thrice as much as the skirt.
How much more did the blouse cost than the skirt?
4 units = $104
B
1 unit
$104
S
?
= $104 ÷ 4
= $26
2 units = $26 x 2
= $52
The blouse cost $52 more than the skirt.
Multiple Model Practice 2
A vendor sold twice as many papayas as mangoes.
He also sold thrice as many apples as mangoes.
If 48 papayas were sold, how many fruits were sold altogether?
2 units = 48
M
1 unit
P
A
48
?
= 48 ÷ 2
= 24
6 units = 24 x 6
= 144
144 fruits were sold altogether.
Multiple Model Practice 3
Lynn saved 4 times as much money as Wendy.
If Lynn saved $160, how much did they save altogether?
$160
4 units = $160
L
1 unit
?
W
= $160 ÷ 4
= $40
5 units = $40 x 5
= $200
They saved $200 altogether.
Multiple Model Practice 4
Amy bought twice as many stickers as Betty. Betty bought three times as
many stickers as Chloe. If they bought 140 stickers altogether, how many
more stickers did Amy buy than Chloe?
C
B
10 units = 140
?
1 unit
= 14
140
5 units
A
= 140 ÷ 10
= 14 x 5
= 70
Amy bought 70 more stickers than Chloe.
Difference Model
Difference Model Example 1
A belt and a tie cost $100. The belt costs $18 more than the tie.
What is the cost of the tie?
?
2 units = $100 - $18
T
= $82
$100
B
18
1 unit
= $82 ÷ 2
= $41
The tie costs $41.
Difference Model Example 2
A table cost $98 more than a chair. Mrs Li paid $398 for a table and 2
chairs. How much did each chair cost?
$98
T
C
C
?
3 units = $398 - $98
= $300
$398
1 unit
= $300 ÷ 3
= $100
Each chair cost $100.
Difference Model Example 3
Joe had $15 more than Doreen but $50 less than Mark. If they had
$290 altogether, how much money did Doreen have?
D
?
3 units = $290 - $50 - $15 - $15
= $210
J
$290
$15
1 unit
= $210 ÷ 3
= $70
M
$15
$50
Doreen had $70.
Difference Model Example 4
The sum of 2 numbers is 100. The difference between the 2 numbers
is 18. What is the bigger number?
?
B
2 units = 100 + 18
= 118
18
100 + 18
S
18
1 unit
= 118 ÷ 2
= 59
The bigger number is 59.
Try It Out!
Practice questions
Difference Model Practice 1
A TV and a DVD player cost $2020. The TV costs $180 more than the
DVD player. What is the cost of the DVD player?
2 units = $2020 - $180
TV
$180
= $1840
$2020
DVD
?
1 unit
= $1840 ÷ 2
= $920
The DVD player costs $920.
Difference Model Practice 2
The total cost of 3 items, A, B and C is $43.
Item A costs $7 less than item B. Item B costs $5 less than item C.
What is the cost of item C?
3 units = $43 - $7 - $7 - $5
A
B
= $24
$43
$7
1 unit
= $24 ÷ 3
= $8
C
$7
?
$5
$8 + $7 + $5 = $20
Item C costs $20.
Difference Model Practice 3
There is a total of 100 hens and ducks in a farm.
There are 40 more hens than ducks. How many hens are there in the
farm?
?
2 units = 100 + 40
H
40
= 140
100 + 40
D
40
1 unit
= 140 ÷ 2
= 70
There are 70 hens.
STAR approach
Study the problem.
- What is the important information given?
- How can I connect, link or organise the
information?
Think of a plan.
- What is the missing information I need to
find?
- What strategies should I use to find the
missing information?
STAR approach
Act on the plan.
- How do I solve the problem?
- Does each step makes sense?
Reflect on solution.
- How do I know if I had answered the
problem?
Past PSLE Question
In an aquarium, there are swordtails and guppies.
25% of the fishes are swordtails.
If an equal number of swordtails are put into the aquarium, what
percentage of the fish will be guppies?
5 units = 100%
G
100%
S
= 100% ÷ 5
= 20%
?
3 units = 20% x 3
G
= 60%
100%
S
1 unit
60% of the fish will be guppies.
Past PSLE Question
A box weighs 4 times as much as a bag. The difference in their
weights is 7.8 kg. What is the weight of the box?
?
Box
3 units = 7.8 kg
1 unit
= 7.8 kg÷ 3
= 2.6 kg
Bag
7.8 kg
4 units = 2.6 kg x 4
= 10.4 kg
The box is 10.4 kg.
Thank You