Purpose

In this activity we work with four digit numbers, adding and subtracting 1, 10, 100 and 1000 to these.

Achievement Objectives

NA3-4: Know how many tenths, tens, hundreds, and thousands are in whole numbers.

Specific Learning Outcomes

add and subtract the numbers 1, 10, 100 and 1000 to four digit numbers

Required Resource Materials

Two dice: * one with number operations: +,+,+,-,-,-, one with numbers: 1, 10, 10, 100, 100, 1000 * Blackboard or whiteboard

Activity

- Write a 4 digit number on the board, for example:
- Ask a volunteer to roll the two dice and write the resulting problem beside the original number. For example if the dice showed + and 100:
3067 + 100 =

- Ask the students what the answer is, getting them to explain their thinking. Record the answer.
- Roll the dice again and repeat, using the previous answer as the starting point.

3067 + 100 = 3167

3167 – 1000 = 2167

2167 – 10 = 2157 etc. - Repeat the activity with a different starting number.

3067

3067 + 100 = 3167

### Extension:

Once students are familiar with this activity they can be provided with a string of numbers and asked what the dice must have rolled to come up with these answers.

For example:

4582

4482 dice must have rolled – and 100

5482 dice must have rolled + and 1000

5481 dice must have rolled – and 1 etc.