A major manufacturer of golf equipment is considering three designs for a new driver: Design A, Design B, and Design C. Each design differs slightly in terms of the material used to construct the driver's head and shaft. The company would like to know if there is any difference in the overall driving distance for the three designs. Twelve PGA Tour players who represent the company were asked to test each model. After a warm-up period, each player hit each a drive with one of the new designs in a randomly selected order, and the overall distance (in yards) was recorded. The results follow.
Design A __________ Design B __________ Design C
306 ............. 323 ............. 320
279 ............. 313 ............. 289
293 ............. 318 ............. 314
277 ............. 288 ............. 282
281 ............. 286 ............. 287
272 ............. 312 ............. 283
297 ............. 326 ............. 332
271 ............. 306 ............. 284
279 ............. 325 ............. 294
323 ............. 319 ............. 289
301 ............. 307 ............. 293
At the .05 level of significance, test whether the mean driving distance is the same for the three designs?