Question

The finance manager of a corporation claims that, on average, accounts payable are GHS
185. An auditor checked a random sample of 21 of these accounts. The sample mean was GHS
206.58 and the sample standard deviation was GHS 46.42. Assume that the population
distribution is normal. Test at the 0.05 significance level against a two-sided alternative the
null hypothesis that the population mean is GHS 185.
B) A small political party expects to gain 20% of the vote in by-election. A particular candidate
from the party is about to stand in a by-election in Subin-East, and has commissioned a survey
of 200 randomly selected voters in the constituency. If 44 of those interviewed said they would
vote for the candidate in the forthcoming by-election, test whether this would be significantly
above the national party’s claim. Use a test at the 5% significance level.

Answer 1