JIT$/$lean system uses kanban cards to authorize production and movement of materials. In one portion of the system, a work centre ses an average of $105$ pieces of a part per hour. The manager has assigned a safety factor of $0\mathrm{.}50.$ Standard containers are designed hold five dozen pieces each. The cycle time for a kanban is $117$ minutes.

low many kanbans are needed? $($Round the final answer to the nearest whole number.$)$

lumber of Kanbans