Mathematics 9709 · AS & A Level · Hypothesis testing

Hypothesis testing — practice question

The numbers of green sweets in 200 randomly selected packets of Frutos are shown in the table.
(a)[3]

Calculate an unbiased estimate of the population mean for the number of green sweets in a packet of Frutos, and demonstrate that an unbiased estimate of the population variance is $0.783$ correct to $3$ significant figures.

(b)[1]

State suitable null and alternative hypotheses for this test.

(c)[4]

Show that Anji’s test result is significant at the $5\%$ level but not at the $1\%$ level.

(d)[1]

Given that Anji made a Type I error, explain how this proves that the significance level she used in her test was not $1\%$.

Worked solution & mark scheme

This 9-mark question has a full step-by-step worked solution and mark scheme. One marking point: Find the sample mean, $\hat{\mu}=\frac{307}{200}=1.535$

  • Full mark scheme, point by point
  • Step-by-step worked solution
  • Write your answer & get it marked instantly by AI