T or Z? The Showdown
Read real-world business scenarios, spot the key statistical clues, and decide: should you use a T-test or a Z-test?
How It Works
- You will face 10 randomly selected business scenarios
- Each scenario provides sample size, and whether the population standard deviation is known
- Choose T-test or Z-test for each scenario
- Earn 10 points for each correct answer (100 max)
- After all rounds, receive a letter grade and a decision rule recap
Game Over!
You scored out of 100
Decision Rule Summary
Use Z-test when:
σ (population standard deviation) is KNOWN
Use T-test when:
σ is UNKNOWN (using sample standard deviation s instead)
Note: Sample size matters less than whether σ is known. Even with large n, if σ is unknown, use the T-test.