Step $3$ is the bottleneck with the longest processing time $=10$ minutes$/$unit $=6$ units$/$hour

Without an inventory buffer, what is the average capacity of the bottleneck in units$/$hour$?$

$($Hint: capacity is in units$/$time$.$ Calculate how many units can be produced by Step $3$ in $1$ hour and $15$ minutes $(1\mathrm{.}25$ hours$)?$ Keep in mind that, during $15$ minutes $(0\mathrm{.}25$ hours$),$ Step $3$ cannot produce anything because Step $2$ is being maintained.$)$