A hole - punch machine is set to punch a hole 1.84 centimeters in diameter in a strip of sheet metal in a manufacturing process . The strip of metal is then creased and sent on to the next phase of production , where a metal rod is slipped through the hole . It is important that the hole be punched to the specified diameter of 1.84 cm . To test punching accuracy , technicians have randomly sampled 12 punched holes and measured the diameters . The data in centimeters ) follow . Use an alpha of .10 to determine whether the holes are being punched an average of L.84 centimeters , Assume the punched holes are normally distributed in the population . 1.81 1.89 1.86 1.83 1.85 1.82 1.87 1.85 1.84 1.86 1.88 1.85

9.15 A hole-punch machine is set to punch a hole 1.84 centimeters in diameter in a strip of sheet metal in a manufacturing process. The strip of metal is then creased and sent on to the next phase of production, where a metal rod is slipped through the hole. It is important that the hole he punched to the specied diameter of 1.84 cm. To test punching accuracy, technicians have randomlyr sampled 12 punched holes and measured the diameters. The data {in centimeters) follow. Use an alpha of .10 to determine whether the holes are being punched an average of 1.84 centimeters. Assume the punched holes are normally distributed in the population. 1.81 1.89 1.86 1.83 1.85 1.82 1.87r 1.85 1.84 1.86 1.88 1.85