dolution

You are a supplier of Computer circuit boards (CCBs). Production of the circuit boards consists of several steps – Surface Mounting, Baking, and Final Assembly. Surface Mounting puts integrated circuits (ICs) and other components on a CCB. These CCBs are then Baked as a batch and kept in an oven for some time so that the ICs are soldered onto the CCBs. Finally, these CCBs are taken and manually assembled into a case, and wired with connectors. The processing rate at the Surface Mounting station is of 10 CCBs/minute, the processing rate for Baking is of 2 CCBs/minute, and the processing rate for Final Assembly is 4 CCBs/minute. If there are on average 20 units of WIP and the system is working at capacity, what is the throughput time for CCBs?