Waiting time for checkout line at two stores of a supermarket chain were measured for a random sample of customers at each store. The chain wants to use this data to test the research (alternative) hypothesis that the mean waiting time for checkout at Store 1 is lower than that of Store 2.

Store 1 (in Seconds)

461

384

167

293

187

115

195

280

228

315

205

197

Store 2 (in Seconds)

264

308

266

224

244

178

279

289

253

223

a.What are the null and alternative hypothesis for this research?

b.What is the sample mean waiting time for checkout line and the sample standard deviation for the two stores?

c.Compute the test statistic t used to test the hypothesis.