A manufacturer believes that a new promotional campaign will improve the favourable perception of its product. Before the campaign, a sample of 500 consumers showed that 25% had favourable reactions towards the product. After the campaign, a sample of 400 consumers showed that 32% had favourable reactions towards the product.

• Construct a 93% confidence interval for the difference in the proportion of consumers with favourable reactions towards the product before and after the promotional campaign.
  • Enter the lower limit in blank #1. Round your final answer to 2 decimal places and include units.
  • Enter the upper limit in blank #2. Round your final answer to 2 decimal places and include units.
• Interpret the confidence interval.
  • Enter your answer in blank #3.
• Did the promotional campaign increase the proportion of consumers with favourable reactions towards the product? Explain.
  • Enter your answer in blank #4.