Level 4: Comparing Values and Following Multi-Step Graphics
What this level asks
Level 4 graphics hold more entries, and questions ask you to compare two or more items, find a difference, or follow a short procedure with a couple of decisions. The data is still straightforward, but you must track more than one piece of information at a time.
Concepts to know
- Comparison language: "More than," "less than," "twice as many," and "combined" each require a specific operation.
- Differences: Subtract the smaller value from the larger when asked "how many more."
- Totals: "Combined" or "altogether" means add the relevant entries.
- Simple flowcharts: Follow arrows; a diamond shape is usually a decision point with two exits.
- Legends and keys: A symbol or color stands for a category; match the symbol before reading values.
Traps to watch for
- Adding the wrong set: Only sum the categories the question names, not the whole column.
- Confusing a total with a difference: "How many more" is subtraction; "how many in all" is addition.
- Skipping a decision: In a flowchart, missing a yes/no branch sends you to the wrong outcome.
- Misreading grouped bars: Confirm which bar in a pair belongs to which legend entry.
Rule of thumb
Write the operation before you compute: if the question says "more," plan a subtraction; if it says "combined," plan an addition. Naming the operation first prevents most errors.
Worked example: A bar chart shows morning sales of 40 and afternoon sales of 65 for one product. Question: how many more were sold in the afternoon? The phrase "how many more" signals subtraction: 65 − 40 = 25.
Level 6: Multi-Panel Graphics and Cross-Referencing
What this level asks
Level 6 presents denser material: tables with many rows and columns, paired or stacked charts, and graphics that must be read together. Questions often require combining information from two places, such as a chart plus a note, or two columns in a large table.
Concepts to know
- Cross-referencing: Use a value from one part of the graphic to find a related value elsewhere, such as a code that maps to a description.
- Stacked bars: Each segment is a portion; the total height is the sum. To compare segments, read segment heights, not top edges.
- Footnotes and notes: Small print often changes how a value should be interpreted.
- Filtering large tables: Scan a single column for the target value, then read across the row.
- Percentages of a whole: Confirm what the base (the whole) is before interpreting a percentage.
Traps to watch for
- Reading a stacked segment from the axis: The lower segment can be read from the axis, but upper segments must be measured as differences between boundary lines.
- Ignoring a footnote: A note like "figures exclude returns" can invalidate an otherwise reasonable answer.
- Using the wrong base: A percentage of total sales differs from a percentage of units sold.
- Mismatched panels: Two charts may use different scales or time periods; check before comparing.
Rule of thumb
Trace the path explicitly: note where the first fact lives, note where the second lives, and state the link between them before answering.
Worked example: A stacked bar shows Product X total height at 50, with a lower segment ending at 20. The upper segment is 50 − 20 = 30, not 50.