In a crank and slotted lever quick return motion mechanism, the distance between the fixed centres  O and  C  is 200 mm. The driving crank  CP  is 75 mm long. The pin  Q  on the slotted lever, 360 mm from the fulcrum  O, is connected by a link  QR  100 mm long, to a pin  R  on the ram. The line of stroke of  R is perpendicular to  OC  and intersects  OC  produced at a point 150 mm from  C. Determine the ratio of times taken on the cutting and return strokes.