Problem-Solving and Data Analysis practice question

Answer: A. The difference is small and the samples are small, so it may well be due to chance; more data would be needed to conclude that left-handed students at the school are taller.

A 1 cm gap between two groups of 20 is well within what random variation produces.

Why the other answers are wrong

B. Left-handed students at the school are definitely taller on average.

Small samples and a small gap cannot support 'definitely'.

C. Being left-handed causes greater height.

No causal claim can come from an observed difference, let alone one this small.

D. Right-handed students at the school are taller on average.

The sample showed the reverse, and even that is not reliable.

More Problem-Solving and Data Analysis questions

• Very hard
  An item priced at $200 is first marked down by 20%, and then an additional 10% is taken off the reduced price.…
• Very hard
  A data set of 6 test scores has a mean of 78. After a 7th score is added, the mean rises to 80. What was the 7…
• Very hard
  If one of the chips that failed inspection is selected at random, what is the probability that it was produced…
• Very hard
  The regular price of a bicycle at a shop was increased by 25%. Later, during a sale, this increased price was …
• Very hard
  What is the result when the mean number of pets is subtracted from the median number of pets?
• Very hard
  What is the value of x?