From a random sample of 500 Montrealers, 400 indicated that they were in favour of the proposed policy to ban single-use plastic bags on the island. Test at the 10% significance level a politician's statement that "those who are in favour of this policy represent more than 85% of the population."

Formulate the null and alternative hypotheses. [2 marks]

State the decision rule for this test. [2 marks]

Calculate the appropriate statistic for testing the null hypothesis.