Confirming a chart represents the data

Name:

Date:

Class:

Quick Questions

Shade in the A or B circle for each question.

1. A bar chart shows Maths = 80, but the source table says Maths = 88. What does this tell you?

A The chart is representative because the bar is close enough to the table value

B The chart is not representative because a plotted value does not match the table

2. A column chart's y-axis starts at 70 instead of 0, which makes a small difference look huge. What should you check?

A Check the axis start and scale, because a truncated axis can exaggerate differences

B Nothing needs checking, because the axis start never changes how the data looks

3. A pie chart of sales by category shows slices that add up to 112%. What is the problem?

A This is fine, because pie chart slices can add up to more than 100%

B The totals do not add up, so the chart does not match the source data

4. Your table has 5 categories, but the chart only shows 4. Which action best confirms the chart is representative?

A Compare the chart categories with the table and add the missing category

B Leave the chart as it is, because 4 categories are enough

5. Which chart type best suits showing how daily temperature changes across a week?

A A line chart, because it shows change over time

B A pie chart, because it shows each day's temperature as a slice

Match the Pairs

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

Left column		Right column
1representative chart		AA check that the total of the source table equals the total shown in the chart's data, to confirm the totals add up
2=SUM(B2:B6)=SUM(C2:C6)		BThe chart type does not suit the data. A pie chart shows parts of a whole, so a line or column chart should be used to show change over time.
3Check that the chart's axis starts at zero so bar lengths are not exaggerated		CAxis minimum = 0
4Compare each plotted value with its matching cell in the source table		D=B3=D3
5Source total = 250, chart bars add up to 310		EThe totals do not match, so a value has been plotted wrongly, doubled or added by mistake. Check each bar against the table and correct it.
6Pie chart used to show daily temperatures across 30 days		FA chart whose plotted values, axis scales and categories all match the source data, so it shows the data truthfully

Definitions

representative chart

Fill in the Blanks

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

=___(B2:B9)

=_____(B2:B9)

=__(SUM(B2:B9)=SUM(C2:C9),"Match","Check")

=___(B2:B9)

Spot the Error

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

Question 1

A sales = [12, 18, 9, 15]

B shown = [12, 18, 9, 15]

C print(sum(sales), sum(shown))

D match = sales != shown

E print(match)

Question 2

A values = [52, 55, 53]

B axis_start = min(values)

C if axis_start != 0:

D print('Truncated axis')

Question 3

A parts = [40, 35, 25]

B total = sum(parts)

C if total = 100:

D print('Pie adds to 100%')

Question 4

A kinds = ['Cat', 'Dog']

B counts = [8, 5, 3]

C ok = len(kinds) == len(counts)

D print(ok)

Question 5

A chart = 'pie'

B data = 'sales by month'

C suits = chart == 'line'

D print(suits)

Answer Key

Confirming a chart represents the data

Section A: Quick Questions

B — The chart is not representative because a plotted value does not match the table

A — Check the axis start and scale, because a truncated axis can exaggerate differences

B — The totals do not add up, so the chart does not match the source data

A — Compare the chart categories with the table and add the missing category

A — A line chart, because it shows change over time

Section B: Match the Pairs

representative chart → A chart whose plotted values, axis scales and categories all match the source data, so it shows the data truthfully

=SUM(B2:B6)=SUM(C2:C6) → A check that the total of the source table equals the total shown in the chart's data, to confirm the totals add up

Check that the chart's axis starts at zero so bar lengths are not exaggerated → Axis minimum = 0

Compare each plotted value with its matching cell in the source table → =B3=D3

Source total = 250, chart bars add up to 310 → The totals do not match, so a value has been plotted wrongly, doubled or added by mistake. Check each bar against the table and correct it.

Pie chart used to show daily temperatures across 30 days → The chart type does not suit the data. A pie chart shows parts of a whole, so a line or column chart should be used to show change over time.

Section C: Definitions

representative chart — A chart whose plotted values, axis scales and categories all match the source data, so it shows the data truthfully and does not mislead the viewer.

Section D: Fill in the Blanks

=SUM(B2:B9)

=MAX(B2:B9)

=COUNT(B2:B9)

=IF(SUM(B2:B9)=SUM(C2:C9),"Match","Check")

=MIN(B2:B9)

Section E: Spot the Error

D — The check should confirm the plotted values equal the table values, so it needs == (equal). != returns True when the chart does NOT match the data.

B — A bar chart axis should start at 0 so bar lengths match the data. Starting at the smallest value exaggerates the differences. It should be axis_start = 0.

C — A single = assigns a value and is a syntax error in a condition. To check that the pie slices add up to 100 you need the comparison operator ==.

A — The source data has three categories, so the chart needs all three. Leaving out 'Fish' means a category is missing and the chart does not match the data.

A — Sales by month is data over time, which suits a line chart. A pie chart shows parts of a whole, so it is the wrong chart type here. It should be chart = 'line'.