Numbers is a spreadsheet. Spreadsheets are greet for doing calculations. For charts, they are blunt instruments. The OP should use a dedicated charting application. The charting application,
DeltaGraph, is specifically designed to graph data from
Excel and to do heavily formatted presentation graphs. My favorite charting application is
KaleidaGraph. It will easily replicate the look and feel of the OP's sample chart. Both applications will do science and engineering charts. In particular, the OP's chart is a double-Y line graph.
DeltaGraph and
KaleidaGraph will both do this kind of graph with aplomb.
There are many other charting applications available on the Mac, even a couple of freeware clones of the popular and expensive Windows science/engineering application
Origin.
One should not overlook the $29.99 US wonder,
OmniGraphSketcher from the OmniGroup. This application will produce graphs that have the look and feel of hand-drawn graphs produced by a professional graphic artist. Among is features is the ability to import data from
Numbers.