Year 9 Science · Unit 4 · Lesson 8
Apply Worksheet
Learning Goals
True or False? Fix the false ones
Circle T or F for each statement. If the statement is false, rewrite it correctly on the line below.
A truncated y-axis can make a small difference look much larger than it really is.
Correct it:
If all the numbers in a graph are correct, the graph cannot mislead anyone.
Correct it:
Cherry-picking means choosing only the data that supports your conclusion.
Correct it:
If two things rise together on a graph, one of them must be causing the other.
Correct it:
Scenario
An energy-drink company runs an advertisement with a bar chart titled "Energy boost". Its drink scores 82 and a rival scores 79, but its bar towers over the rival's. The small print shows the vertical axis starts at 78, not 0. The ad shouts "Almost double the boost!"
(a) Identify the single trick the company has used to make its bar look so much taller.
(b) If the chart were drawn honestly, where should the vertical axis start, and roughly how would the two bars then compare?
(c) The claim "Almost double the boost!" is not supported by the numbers 82 and 79. Explain why the words and the data do not match.
1. A climate post shows a temperature graph covering only the last three years to claim "temperatures are falling", while the Bureau of Meteorology record over 100 years shows a clear rise. Explain how showing only a short window distorts the data.
2. Nine staff at a cafe earn $48,000 and the owner earns $480,000. A job ad quotes the mean wage as "$91,200". Explain why the median would be a fairer figure to advertise, and state what the median is here.
Wrap Up
In one sentence, what was the main idea of this lesson?