We at Matrix Math and Model Math have curated a comprehensive list of frequently tested Primary 4 heuristic concepts to assist students in comprehending the fundamental building blocks that constitute complex heuristic problem sums. By mastering the concepts featured in our series of educational videos, we are confident that students can significantly enhance their mathematical proficiency and excel in this subject. We aim to provide weekly updates to this page, so please visit us regularly for new learning materials.
Primary 4
Math Tuition Lesson 4
Stacking model
In Primary 3, students learned about the Comparison Model for comparing the values of two different items, such as “a jar has 3 more cookies than a can.” Now, we would like to introduce a new method called the Stacking Model. This technique is used when comparing multiple items of the same type, for instance “3 jars have 5 more cookies than 3 cans.” The Stacking Model provides a visual representation and makes it easier to understand and compare multiple items.
Direct supposition
The Supposition concept can be a challenging one for students. At Model Math, we first introduce this idea in Primary 2 and gradually build upon it through repetition and more complex problems. This video example demonstrates the basics of the Supposition concept.
Supposition with penalty
The Supposition concept can be a challenging one for students. At Model Math, we first introduce this idea in Primary 2 and gradually build upon it through repetition and more complex problems. In Primary 4, we introduce Supposition with Penalty, which is a higherlevel problemsolving technique that utilises the Supposition concept. It is common for students to need more than one lesson to fully grasp this concept, so we will be revisiting it in future lessons.
Math Tuition Lesson 6
External transfer, given difference
Peter had 20 more stickers than John at first. John then lost 169 stickers in a game. Peter now had four times as many stickers as John. How many stickers did John have at first?
External transfer, given units
In a container, the number of sweets was five times the number of chocolates. After John took out 26 sweets, there were 30 more sweets than chocolates. How many sweets were there at first?
Math Tuition Lesson 7
External transfer, unchanged difference
Shop A and Shop B had 75 kg and 54 kg of flour, respectively. After both shops sold the same amount of flour, Shop A had four times as much flour as Shop B. How much flour did each shop sell?
Internal transfer, total unchanged
Peter had $52 and Yenni had $26. After Peter gave some money to Yenni, Yenni had $10 more than Peter. How much did Peter give to Yenni?
Approximation & Estimation

An even number is 500 when rounded off to the nearest hundred. What is the greatest possible value of the even number?

Which is the best estimate for 55 x 42?
Math Tuition Lesson 8
Internal Transfer, given units
Bottle A contained four times as much water as Bottle B at first. After 12 L of water was transferred from Bottle A to Bottle B, there was an equal amount of water in both bottles. How much water was there altogether?
Math Tuition Lesson 9
Listing for highest common factors
Peter wants to lay his floor with square carpet tiles. The rectangular shaped floor measures 160 cm by 90 cm.
a) Find the largest possible length of the side of each carpet tile.
b) Find the number of tiles that are needed to cover the floor.
Total concept, regrouping
Amber received $12 for every belt she sold. She also received a bonus of $50 for every 8 belts she sold. She sold 84 belts. How much money did she receive altogether?
Total concept, regrouping
Amber is selling frying pans. For every frying pan she sells, she will earn $6. She will also earn an additional $15 for every 7 pans she sells. If she sells 23 pans, how much will she earn in all?
Math Tuition Lesson 10
Comparison of Quantity and Units
Peter had three times as many stickers as Yenni. John had 63 fewer stickers than Peter. The three children had 119 stickers altogether. How many more stickers did Yenni have than John?
Math Tuition Lesson 11
Shortage and Surplus, listing method with no fixed groups
Shortage and Surplus, units method
Yenni had some money. She wanted to buy 16 markers but was short of $9. In the end, she bought 9 markers and had $5 left. How much money did Yenni have at first?
Shortage and Surplus, listing method fixed number of groups
Math Tuition Lesson 12
Constructing parallel lines
Identifying perpendicular lines
Constructing angles
Math Tuition Lesson 17
Fractions as Part of Remainder with Changing Denominator
Fractions as Part of Remainder with Redrawing Remainder
Yenni had some money. She wanted to buy 16 markePeter had some beads. He used 1/5 of the beads and gave 1/3 of the remainder to Yenni. Peter had 8 beads left. How many beads did Peter have at first?
Total Concept, Direct Application
Math Tuition Lesson 20
External transfer with 1 group unchanged
External Transfer with 1 group unchanged.
The number of apples is 2/5 the number of pears in a basket. 6 more pears are added to the basket and the number of apples is 2/7 the number of pears. How many apples and pears were in the basket at first?
Internal Proportion Transfer
Math Tuition Lesson 21
Decimals, Estimation and Approximation
a) A ribbon is 2.33 m when rounded off to 2 decimal places. What is the smallest possible length of the ribbon?
b) Yenni’s mass is 47.6 kg when rounded off to the nearest tenth. What is her largest possible mass? Leave your answer in 2 decimal places.