9231 P43 - Jun 2025 - Q4 - 8 marks
6657
A researcher claims that older people take longer to react to a sudden loud noise than younger people. To investigate this, the researcher randomly selects 6 people over 50 years old and 8 people under 25 years old and records their reaction times, in milliseconds, to a sudden loud noise. The reaction times are as follows.
Over 50 | 198 | 212 | 217 | 229 | 235 | 242 | ||
|---|---|---|---|---|---|---|---|---|
Under 25 | 178 | 181 | 183 | 192 | 203 | 209 | 223 | 231 |
Carry out a Wilcoxon rank-sum test at the \(5 \%\) significance level to test the researcher's claim.
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