Match the graphic to the data
Pick the form first — the wrong choice scores nothing however neat. A line graph plots a continuous quantity changing over time (a trend). A bar chart compares separate categories by bar height. A pie chart shows how a single whole divides into parts (slices of one circle). A flow chart shows a process with decisions that branch. A sequence drawing shows ordered steps. Ask: trend, comparison, parts of a whole, or a process?
Build a pie: value ÷ total × 360
Draw a pie by converting every value into a sector angle, not by guessing. (1) Add the values for the total. (2) For each category, angle = (value ÷ total) × 360°. (3) Check the angles sum to 360° — a self-check that catches errors. (4) Set each sector with a protractor from one radius. (5) Label every sector (a key or the value). Example: 20/15/15/10 of 60 gives 120°, 90°, 90°, 60° (sum 360°). Convert every value, not just the first.
Standardised signs — shape and colour ARE the message
A standardised sign has a shape and colour agreed to a standard, so it is read instantly, is language-independent and meets safety/legal rules. Safety signs: prohibition (red circle + bar = must NOT), warning (yellow triangle = hazard), mandatory (blue circle = must DO), safe condition (green square = exit), fire (red square). It also covers hazard, recycling, care and flow-chart symbols. Decode shape + colour first.
Drawn from real examiner reports.
Wrong chart type for the question
Asked for a pie chart, many candidates draw a bar chart (or the reverse) and score nothing — the graphic can be neat but is the wrong form for what was asked. The cause is not reading the command: parts of a whole → pie, compare categories → bar, trend over time → line. Check which chart is required, and that the data type matches, before drawing.
s23 P53 QB4d — asked for a pie chart, a significant number drew a bar chart and scored nothing.
Only the first pie sector converted
Candidates who pick a pie often get most sector angles wrong — one set roughly right and the rest estimated by eye, so the slices do not fit the circle. The cause is skipping the conversion: each value must become (value ÷ total) × 360°, for every category. Check the angles sum to 360° (if not, one is wrong), then set each with a protractor.
s23 P53 QB4d — candidates commonly got one sector right but the remaining angles wrong, not converting each value to its share of 360°.
Decision drawn as a rectangle
Flow-chart questions recall the standard shapes. The trap is the process box vs decision diamond: a rectangle is a process; a diamond is a decision (a yes/no question that branches). Drawing a decision as a rectangle removes the branch and breaks the logic. Candidates also omit the feedback loop (returns flow on a failed check) and any delay step.
w23 P53 QB5d–e — flow-chart symbols, the decision box, feedback loop and delay time were tested and recall-based, with symbols and the loop commonly wrong or omitted.
Pie sectors unlabelled or drawn by eye
Two finishing errors lose easy marks on a pie. First, drawing slices by eye instead of setting each angle with a protractor from one radius, so the sectors do not match the calculated angles. Second, leaving it unlabelled — every sector needs a key or its value, or the reader cannot read it. Convert, set with a protractor, then label.
Standard signs and symbols confused
Signs and symbols are recall, and marks go when they are swapped. Keep the safety code straight — prohibition red circle + bar, mandatory blue circle, warning yellow triangle, safe condition green square, fire red square — and know the standard hazard symbols such as flammable. A triangle for prohibition, or blue for warning, loses the mark.
w23 P53 QB5d — standardised symbols (e.g. the flammable symbol) are tested and recall-based.
Pie charts cannot show change over time
A pie chart does not show a trend over time. It shows the parts of one whole at a single moment — each category's share of the fixed total that fills the circle — with no time axis. A quantity changing over time needs a line graph. The tell: change over time → line graph; proportions of a whole → pie.
Draw what is asked, convert, label
Bank marks in order: draw the graphic actually asked for (the wrong form scores nothing); match form to data (whole = pie, compare = bar, trend = line, process = flow chart); for a pie convert every value and check they sum to 360°; then label fully.
Draw with instruments, not freehand
Data-graphics marks reward neat, instrument-drawn work: a protractor for pie sectors, a ruler for bar heights and axes, standard symbols for a flow chart — never freehand. A ruled, correctly-typed, fully-labelled graphic is the base competence expected.
Use the exact standard symbol
For a flow chart use the correct shape: a diamond for a decision (not a rectangle), a rounded terminator for start/stop — and draw the branch and feedback arrows. For signs, use the standard shape and colour. The exact symbol scores.
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