Skip to content
Part ACSIR NET September 2022must-be-true-vs-can-be

Must be true vs can be

The arithmetic mean of five numbers is zero. The numbers may not be distinct. Which of the following must be true?

  1. A.The product of the numbers is zero
  2. B.At most two of these numbers are positive
  3. C.There cannot be exactly one zero
  4. D.There cannot be exactly one non-zero number✓ Correct

You have the answer. Trap Analysis is why the other three were written.

Not a worked solution repeated four times — the specific reasoning error each wrong option was built to reward, and why this one tests what the inference means.

See pricing

50 are analysed free — try those first.

The trap it tests

What the inference means

p-values, size, power and error types say specific things. This was not one of them.

Drill statements like this

Last revised . Found a mistake? Tell us — corrections are the fastest thing we act on.

ShareWhatsAppTelegram