Hi I am analysing some results and am very new at this thing. I have grown bacteria on different agar mediums from samples before and after washing hands. I am looking at colonies of bacteria and if the number of colonies change before and after washing hands. Increase or decrease is possible.

Does anyone have any suggestions as to what stats tests I should use to get an accuarate analysis and any other tips to do with this?

Also as the numbers are very large i.e. 6.7x10 to the power of 5 it is all recorded in standard form, would this be a problem?

Any help would be greatly apreciated and if I can help with anything in the future just ask.