A cognitive psychologist investigated the impact of ambient scents on problem-solving speed using a repeated measures design, where the same group of participants completed tasks under two different environmental conditions.

• In the first condition, participants were placed in a room infused with a lavender scent and asked to solve a set of 10 complex logic puzzles.
• In the second condition, participants were placed in a room infused with a peppermint scent and asked to solve a different set of 10 logic puzzles of matched difficulty.

The psychologist recorded the time taken (in seconds) by each participant to successfully complete the puzzles.

Table 1: Mean completion times (seconds) and standard deviations