With compasses and using the latitude scale draw arcs of 41NM from SHA and 30NM from CRK.   If the aircraft is heading West and the ranges are decreasing it must be at the easterly intersection of these two arcs: 52º15’N 008º05’W.

 

At the Easterly intersection which CAN be plotted on the chart and at the given coordinates, on a heading of 270 the DME distances would be decreasing (as the aircraft is flying into the plotted circles).