16Hit1600
Problem-Solving and Data AnalysisEasyRecognising a random sample

Problem-Solving and Data Analysis practice question

A head teacher wants a random sample of 20 pupils from the school. Which method gives a random sample?

  1. A. Putting every pupil's name in a box and drawing 20 without looking.Correct
  2. B. Choosing the first 20 pupils to arrive one morning.
  3. C. Asking for 20 volunteers.
  4. D. Choosing the 20 pupils with the highest marks.

Answer: A. Putting every pupil's name in a box and drawing 20 without looking.

Every pupil has the same chance of being drawn.

Why the other answers are wrong

B. Choosing the first 20 pupils to arrive one morning.
Early arrivals are not typical of everyone.
C. Asking for 20 volunteers.
Volunteers choose themselves.
D. Choosing the 20 pupils with the highest marks.
That picks a particular group on purpose.

More Problem-Solving and Data Analysis questions

Not affiliated with the College Board. SAT is a trademark of the College Board.