1. A worker is currently responsible for tending two machines in a certain production cell. The service time per machine is 0.35 min and the time to walk between machines is 0.15 min. The machine automatic cycle time is 1.90 min. If the worker's hourly rate is $12/hr and the hourly rate for each machine is $18/hr, determine: (a) the current hourly rate for the cell (b) the current cost per unit of product, given that two units are produced by each machine during each machine cycle. (c) What is the percentage of idle time of the worker? (d) What is the optimum number of machines that should be used in the cell, if minimum cost per unit of product is the decision criterion? 2. The analyst in X Company wishes to assign a number of similar facilities to an operator based on minimizing the cost per unit of output. A detailed study of the facilities revealed the following: Loading machine standard time = 0.34 minutes Unloading machine standard time= 0.26 minutes Walk time between two machines = 0.06 minutes Operator rate = $12.00 per hour Machine rate (both idle and working) $18.00 per hour Power feed time 1.48 minutes How many of these machines should be assigned to each operator? 3. A study revealed that a group of three semiautomatic machines assigned to one operator operates 70 percent of the time unattended. Operator service time at irregular intervals averaged 30 percent of the time on these three machines. What would be the estimated machine hours lost per eight-hour day because of lack of an operator? 4. In the X Company, a worker was assigned to operate three similar facilities. Each of these facilities is down at random times during the day. A work sampling study indicated that on the average the machines operate 60 percent of the time unattended. Operator attention time at irregular intervals averages 40 percent. This arrangement results in the loss of about 14 percent of the available machine time due to machine interference. If the machine rate is P200 per hour and the operator rate is P30 per hour, what would be the most favorable number of machines (from an economic standpoint) that should be operated by one operator