Representing numbers in different ways
In a nutshell
You can represent numbers in many different ways: number lines, tally charts, counters, place value charts and models. Visual representations can help you to understand place value, and are useful when introducing new topics such as the four operations.
Number lines
You can represent numbers by using a number line. Count the marks on the number line to determine what value each jump of a small division represents.
Example 1
What number is represented on the following number line?
There are 10 "jumps" between the numbers 600 and 650. You can use this information to work out what each small "jump" is.
650−600=5050÷10=5
This means that the number line goes up in fives. The arrow points the number seven marks away from 600.
600+(7×5)=635
This means that the number represented on the number line is 635.
Counters
Counters are used as visual representations of numbers. The following number counter represents the number 66. There are 6 full rows of 10 and 6 ones.
(6×10)+6=66
Tally charts
Tally charts use lines to represent values. Each line represents a one. When there are five tally lines, the fifth is marked across the previous four, looking like a "gate". Grouping tally charts in fives makes it quicker to add up the total at the end, as long as you know your times tables.
Example 2
What number is represented below using the tally charts?
Counting up in fives, the 8 "gates" represent 40 and the 3 lines represent 3.
The number represented on the tally chart is 43.
Part whole model
Part whole models show a full number and the parts that make up that number. The smaller numbers always make up the bigger number using this model. A part whole model can help you understand how addition and subtraction work.
Example 3
Construct a part whole model for the calculation
17+38=55
The two smaller numbers that make up the larger number are 17 and 38. Place them into a part whole model connecting each of them to the bigger number, 55.