Primary 3 Heuristic Concepts

QUANTITY DIFFERENCE AND INTERNAL TRANSFER

John had $86 more than Peter at first. How much money must John give to Peter so that he will only have $42 more than Peter?

QUANTITY EXTERNAL TRANSFER, BEFORE CHANGE AFTER

Yenni and Anna had the same amount of money at first. After Yenni used $23 and Anna used $13, the amount of money Anna had left was thrice that of Yenni. How much money did Anna have at first?

QUANTITY INTERNAL TRANSFER

Amber and Yenni had the same amount of money. After Amber gave Yenni $222, she was left with $6088.

(a) How much money did Amber have at first?

(b) How much more money did Yenni have than Amber in the end?

MEASUREMENT, PART AND WHOLE

Amber had 5 m 24 cm of ribbon. She used 28cm to tie a bow and some to tie a present. In the end, she had 50 cm of ribbon left. What was the length of the ribbon that she used to tie the present?

MEASUREMENT, WORKING BACKWARDS

Peter had some water in a tank. He poured away 2 L 450 ml and there was 3 L 30 ml left in the tank. How much water was in the tank at first?

PART AND WHOLE

7843 people were watching a football match. 2142 were women and the rest were men. How many more men than women were there?

FRACTION WITH PART AND WHOLE

Yenni had $790. She donated 3/5 of her money to Elderly Care Centre and the remaining amount of money to Children Care Centre.

(a) Which care centre received less money?

(b) How much money did Elderly Care Centre receive?

(c) How much money did Children Care Centre receive?

FRACTIONS AND COMPARISON MODEL

A fruit seller sold some apples, oranges and pears in a day. The number of apples sold was three times as many as the number of oranges. 5/9 of the fruits sold were pears. How many fruits did the fruit seller sell if he sold 198 apples in a day?

COMMON IDENTITY

The mass of a box and a packet of sweets is 1380 g. The mass of the same box and 2 similar packets of sweets is 2040 g. What is the mass of 1 packet of sweets?

FRACTIONS AND COMPARISON MODEL

A fruit seller sold some apples, oranges and pears in a day. The number of apples sold was three times as many as the number of oranges. 5/9 of the fruits sold were pears. How many fruits did the fruit seller sell if he sold 198 apples in a day?