The following observations were noted from an activity sampling study of a CNC machine: Machine working: 800 Machine idle: 450 a) Determine whether the degree of accuracy of the result on a 95% reliability basis is within 5% (5) b) Determine the limit of error for the activities on a 95% reliability basis. (3) c) Determine the additional number of observations required to obtain a +1% as a limit of error for the activities on a 95% reliabilities basis. d) Calculate the degree of accuracy that will be obtained after the additional observations have been made. Interpret the result. (3) (5) Group QUESTION 2 The readings below were obtained from an activity sampling study: ACTIVITY Operator A Operator B Operator C Working 450 405 510 Unproductive 250 240 300 No tools 108 130 23 Supervision 85 27 Total Observations 52 a) For the entire group, calculate the maximum and minimum percentage values to be expected for each activity @ 95% reliability basis. (10) b) For operator B activities, calculate the maximum and minimum percentage values to be expected @ 95% reliability basis. (10) c) Calculate the additional number of readings required to obtained +3% as a limit of error for the entire group on a 95% reliability basis. (6) d) Calculate the additional number of readings required to obtained 13% as a limit of error for operator A activities on a 95% reliability basis. (4) QUESTION 3 Explain briefly why activity sampling is an acceptable ratio delay study method. (14)