Here are nine original deductive reasoning examples, each with a verdict and the reasoning written out step by step. Every verdict is one of three: follows, does not follow, or cannot be determined. Cover the answer, make your call, then check your reasoning against the steps.
What the three verdicts mean, and how to use these examples
Follows means the statements force the conclusion to be true. Does not follow means the statements rule it out. Cannot be determined means the statements leave the conclusion open: you can imagine it true and imagine it false. If a test offers only "follows" and "does not follow", fold the last two together.
Read the statements once, then write down your verdict before you look at the explanation. Next, say in one sentence why. If your sentence is "it sounds right", you have not finished. A good sentence names either the rule that forces the conclusion or the picture in which it fails.
Examples with all, no and some
Example 1: a valid syllogism
All auditors in the firm have completed the ethics course. Mira is an auditor in the firm. Conclusion: Mira has completed the ethics course.
Follows. Mira belongs to the group of auditors in the firm, and every member of that group completed the course. There is no way to keep both statements true and make Mira the exception.
Example 2: the missing bridge
All couriers carry a scanner. Some people who carry a scanner work nights. Conclusion: Some couriers work nights.
Cannot be determined. The night workers with scanners might all be warehouse staff, or some of them might be couriers. Both pictures fit the statements, so neither answer is forced.
Example 3: "all" does not flip
No intern has admin rights. Everyone with admin rights can delete records. Conclusion: No intern can delete records.
Cannot be determined. The statements say that admin holders can delete, not that only admin holders can. An intern might hold some other permission that allows deletion.
Example 4: "some" and "all" together
Some of the engineers passed the licensing exam. Everyone who passed the licensing exam received a bonus.
Conclusion A: Some engineers received a bonus.
Conclusion B: All engineers received a bonus.
A follows; B cannot be determined. At least one engineer passed the exam, and that engineer received a bonus, which gives A. The statements say nothing about engineers who did not pass, so B could be true or false.
Examples with if-then rules
Example 5: modus tollens
If the alarm is armed, the red light is on. The red light is off. Conclusion: The alarm is not armed.
Follows. Suppose the alarm were armed. Then the red light would be on, and it is not. So the alarm cannot be armed.
Example 6: the converse trap
If a parcel is fragile, it is packed in foam. Parcel 7 is packed in foam. Conclusion: Parcel 7 is fragile.
Cannot be determined. The rule says fragile parcels get foam. It does not say that only fragile parcels do, so a sturdy parcel could also be in foam.
Examples with ordering and wording
Example 7: ordering with a gap
Amit scored higher than Bea. Carla scored lower than Amit. Conclusion: Bea scored higher than Carla.
Cannot be determined. Bea and Carla are both below Amit, and nothing compares them. Put Bea above Carla and the statements hold; put Carla above Bea and they still hold.
Example 8: a ranking that locks into place
Five people stand in a queue. Ravi is ahead of Sam. Sam is directly ahead of Tia. Uma is last. Vera is ahead of Ravi.
Conclusion A: Vera is first.
Conclusion B: Ravi is third.
A follows; B does not follow. Uma takes fifth place. The remaining four must run Vera, Ravi, Sam, Tia, because Vera is before Ravi, Ravi is before Sam, and Tia is right behind Sam.
That puts Vera first and Ravi second, which rules out Ravi in third place. Here the statements settle the order completely, so a conclusion that fails is clearly ruled out and not merely open.
Example 9: what "or" allows
The memo was sent by finance or by legal. Finance sent it. Conclusion: Legal did not send it.
Cannot be determined. An ordinary "or" does not exclude both. Add the words "but not by both" to the first statement and the conclusion follows, so always check whether the wording is exclusive.
What the nine examples have in common
Every verdict above came from the same move: look for a situation in which the statements hold and the conclusion fails. Of the eleven conclusions in these examples, four follow, one is ruled out and six are left open. That mix belongs to this set and says nothing about any particular test. It does show how often a tempting conclusion is simply not forced.
The habit has a research pedigree. Philip Johnson-Laird has argued that our ability to use counterexamples to refute invalid inferences provides a foundation for rationality.
If one example gave you trouble, go to the matching guide.
- Examples 1 to 4 are all/no/some statements, covered in syllogisms, validity and truth.
- Examples 5 and 6 are if-then rules. The step from "not Q" to "not P" in Example 5 is the one Peter Wason's 1968 experiments on conditional rules made famous for being hard, and the full story is in if-then reasoning.
- Examples 7 and 8 are ordering problems, where the question is always how much the statements fix.
- Example 9 is about the wording of "or".
Example 3 is also a permission rule, the kind of everyday rule that Patricia Cheng and Keith Holyoak studied in their 1985 work on pragmatic reasoning schemas. Everyday wording can make a rule feel easier, but the verdict still has to come from the statements alone.
Practise on questions you have not seen
Reading solved examples builds recognition, but only fresh problems show whether you can do it unaided. The JobCannon Deductive Reasoning Test is built around "follows / does not follow" conclusions from a set of statements, with syllogisms, if-then rules and ranking puzzles.
JobCannon's older logical reasoning test is a broader mix that adds analytical puzzles. Both are written in-house, so treat your result as practice feedback. The method behind these answers is in how to solve deductive reasoning questions.