A bike frame has to go through the welding operation. The time in the welding operation is spent as follows: 3 hours waiting in front of the cutting machine for the batch to start, 1 hour waiting for the setup of the machine, 3 hours waiting for the other pieces of the batch to go through cutting, 1 minute at the cutting machine, and 3 hours waiting for the transfer to the welding machine; then, at the welding machine, the unit spends 2 hours waiting in front of the welding machine for the batch to start, 1 hour waiting for the setup of the welding machine, 2 hours waiting for the other pieces of the batch to go through welding, 0.25 minute at the welding machine, and 2 hours waiting for the transfer to the next department.
(a) Calculate the exact total flow time in minutes of the welding operation.
(b) Calculate the exact value added time in minutes of the welding operation.
(c) Calculate the value added percentage (percentage, 5 decimals, i.e. 1.54397%).