| Exam Board | CAIE |
| Module | Further Paper 4 (Further Paper 4) |
| Year | 2022 |
| Session | June |
| Topic | Hypothesis test of a normal distribution |
1 The times taken by members of a large quiz club to complete a challenge have a normal distribution with mean \(\mu\) minutes. The times, \(x\) minutes, are recorded for a random sample of 8 members of the club. The results are summarised as follows, where \(\bar { x }\) is the sample mean.
$$\bar { x } = 33.8 \quad \sum ( x - \bar { x } ) ^ { 2 } = 94.5$$
Find a 95\% confidence interval for \(\mu\).