Your question asks for 20 weights per group - for the sake of keeping things
short this example shows 5 weights per group. Set your data up in the
following manner with WP in cell A2, KO in cell A7, Mouse in cell B1, and
Weight in cell C1:

Mouse Weight
WP 1 2.1
2 3.4
3 1.6
4 1.3
5 4.8
KO 1 1.4
2 1.8
3 1.7
4 1.3
5 2.1

Select the range C1:C11. Go to the Standard Toolbar and click on the Chart
Wizard icon. In Step 1 of 4 of the Wizard, under the Standard Types tab
select the Line - Line Markers Displayed at Each Value chart. Hit the Next
button until the chart appears on your worksheet.

Once the chart appears, click on it once and go to the Standard Toolbar.
Select Chart - Source Data. Under the Series tab select the Category (X)
Axis Labels. Highlight the range A2:B11 and then hit the OK button. The
chart should now have two categories on the X axis - one for WT and one for
KO.

Double-click on the line series. In the Format Data Series dialog box, go
to the Patterns tab and select Line = None. At this point you can continue
to format the chart as you wish by adding data labels, etc. Data labels are
also accessed via the Format Data Series dialog box - Data Labels tab.

You might also want to experiment with creating an XY Scatter chart with the
same data.

----
Regards,
John Mansfield
http://www.pdbook.com


"pathologist" wrote:

I have two groups of different types of mice called WT and KO. I've measured
the weight of twenty from each group. I want to make a chart with the X axis
being "WT" and "KO" and I want to have the Y-axis show all ten data points
for each group. How does one do this? I'm using Exel XP. Thanks.