Unit 7 · Data and Percentage
Eight Swimmers — Who Gets the Highest Score?
Lesson 1 of 3
Data and table questions form a significant part of OC Thinking Skills, and the easiest ones simply reward careful, methodical reading — no complex formulas required, just a clear two-step process.
Ranking from a table with a specific selection rule (e.g. "take the better of two attempts") appears regularly in OC TS as an entry-level data question. The most common mistake is reading one row incorrectly and getting the entire ranking wrong as a result.
The examiner is testing whether you can correctly apply a selection rule to every row in a table, extract all the relevant values, and then rank them accurately — without mixing up the selection step and the ranking step.
A table of numerical results is given with a stated rule (e.g. "faster time counts"). You must apply that rule to every row, then order the extracted values from best to worst. The question asks for a specific placing — 1st, 2nd, or last.
Best approach: Do this in two clean passes. First pass: go through every row and write down the single selected value (the faster time, the higher score, etc.). Second pass: rank those extracted values. Never try to rank while simultaneously extracting — separating the two steps eliminates almost all errors.
Question
Eight swimmers each get two attempts at 50 m; the faster time counts as their result.
| Swimmer | Attempt 1 (s) | Attempt 2 (s) |
|---|---|---|
| 1 | 31.4 | 30.2 |
| 2 | 29.8 | 31.5 |
| 3 | 32.1 | 30.7 |
| 4 | 30.5 | 31.0 |
| 5 | 29.5 | 30.8 |
| 6 | 30.9 | 31.4 |
| 7 | 31.8 | 29.6 |
| 8 | 30.3 | 30.1 |
Who finishes 2nd (silver medal)?
Select an answer to see the explanation.
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