Spotting misleading charts

Name:

Date:

Class:

Quick Questions

Shade in the A or B circle for each question.

1. A column chart's y-axis starts at 95 instead of 0. Two bars show 96 and 100. What does this do?

A Shows the true size of the difference

B Makes a small difference look huge

2. Which chart is more honest about the size of a difference between two bars?

A A bar chart whose axis starts at 90

B A bar chart whose axis starts at 0

3. A pie chart is tilted in 3D so the front slice looks bigger than the back slice. Why is this misleading?

A The slice nearest you looks larger than it really is

B 3D makes every slice the correct size

4. A line graph shows only the 3 best weeks of a school canteen's sales out of 20 weeks. This is an example of...

A A cherry-picked range

B A fair sample of all the data

5. Which is a warning sign that a chart might be misleading?

A The axis has no labels or numbers

B The chart has a clear title and labelled axes

Match the Pairs

Draw a line connecting each item on the left to its match on the right.

Left column		Right column
1Y-axis starts at 90, not 0		AThe axis does not start at zero, so a tiny 3-point difference looks like one bar is several times taller. Fix: start the axis at 0.
23D pie chart tilted back		BY-axis: 0, 20, 40, 60, 80, 100
3Choosing only the good weeks to show a rise in sales is a cherry-picked range		CMissing labels mean the reader cannot tell what the data measures, so they may read it wrongly. Fix: add a title, axis labels and units.
4To show differences fairly, bars should start from zero		DA truncated axis that makes small differences between bars look huge
5Bar chart: axis runs 95 to 100, scores 96 and 99		EA 3D effect that makes slices at the front look bigger than they really are
6Line chart: no title, no axis labels, no units		Fx-axis: Weeks 8 to 10 only (Weeks 1 to 7 left out)

Definitions

misleading chart

Fill in the Blanks

Complete each line of code by filling in the missing parts.

Column chart: Y-axis minimum = _

Chart style: ___ column

Data: B2:B13 (Jan-Dec) Chart range: B2:___

Axis steps: 10, 20, __, 40

Add: Chart Title, ___________, Legend

Spot the Error

Shade in the letter of the line that contains an error.

Question 1

A chart = "column"

B title = "Cans collected by class"

C y_axis_start = 50

D y_axis_label = "Cans"

Question 2

A chart = "bar"

B title = "Canteen sales"

C effect = "3D tilt"

D labels = "on"

Question 3

A chart = "line"

B title = "Daily steps in 2024"

C x_start = "Jan"

D x_end = "Feb"

Question 4

A chart = "line"

B y_min = 0

C y_step = "10, 20, 50, 100"

D y_label = "Points"

Question 5

A chart = "column"

B y_label = ""

C x_label = "Month"

D title = "Pizza prices"

Answer Key

Spotting misleading charts

Section A: Quick Questions

B — Makes a small difference look huge

B — A bar chart whose axis starts at 0

A — The slice nearest you looks larger than it really is

A — A cherry-picked range

A — The axis has no labels or numbers

Section B: Match the Pairs

Y-axis starts at 90, not 0 → A truncated axis that makes small differences between bars look huge

3D pie chart tilted back → A 3D effect that makes slices at the front look bigger than they really are

Choosing only the good weeks to show a rise in sales is a cherry-picked range → x-axis: Weeks 8 to 10 only (Weeks 1 to 7 left out)

To show differences fairly, bars should start from zero → Y-axis: 0, 20, 40, 60, 80, 100

Bar chart: axis runs 95 to 100, scores 96 and 99 → The axis does not start at zero, so a tiny 3-point difference looks like one bar is several times taller. Fix: start the axis at 0.

Line chart: no title, no axis labels, no units → Missing labels mean the reader cannot tell what the data measures, so they may read it wrongly. Fix: add a title, axis labels and units.

Section C: Definitions

misleading chart — A chart whose design, like a cut-off axis, 3D effects or a cherry-picked range, makes the data look different from what it truly shows.

Section D: Fill in the Blanks

Column chart: Y-axis minimum = 0

Chart style: 2-D column

Data: B2:B13 (Jan-Dec)
Chart range: B2:B13

Axis steps: 10, 20, 30, 40

Add: Chart Title, Axis Titles, Legend

Section E: Spot the Error

C — Starting the y-axis at 50 cuts off the bottom of the columns, so small differences look huge. A fair column chart starts at 0: y_axis_start = 0.

C — A 3D tilt makes bars at the front look bigger than bars at the back, so it is hard to compare them fairly. It should be a flat 2D effect: effect = "flat 2D".

D — The title says the whole of 2024, but ending at Feb is a cherry-picked range that hides the rest of the year. The x-axis should end at Dec: x_end = "Dec".

C — An uneven scale squashes some changes and stretches others, which distorts the shape of the line. The steps should be equal: y_step = 10.

B — A missing y-axis label means readers cannot tell what the numbers measure or what units they use. It should say what is measured: y_label = "Cost ($)".