statistics · Year 4 · AC9M4ST01
Reading a graph scale
Before reading any bar or point, read the scale. Graphs often go up in 2s, 5s or 10s, so each gridline is worth more than 1. To find a value, count how many gridlines the bar reaches and multiply by what each gridline is worth. If a scale goes up in 2s and the bar reaches the 4th line, that is 4 × 2 = 8, not 4. Count the lines from zero and stop exactly where the bar ends.
Sample questions
A bar graph's scale goes up in 2s (each gridline is worth 2). A bar reaches gridline number 4 above zero. What value does it show?
- Each gridline is worth 2, not 1.
- The bar reaches 4 gridlines, so 4 × 2 = 8.
Answer: 8
A bar graph's scale goes up in 2s (each gridline is worth 2). A bar reaches gridline number 5 above zero. What value does it show?
- Each gridline is worth 2, not 1.
- The bar reaches 5 gridlines, so 5 × 2 = 10.
Answer: 10
A bar graph's scale goes up in 2s (each gridline is worth 2). A bar reaches gridline number 3 above zero. What value does it show?
- Each gridline is worth 2, not 1.
- The bar reaches 3 gridlines, so 3 × 2 = 6.
Answer: 6