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Electric fields and Millikan's Oil Drop Experiment

Hi there, I'm really stuck on this question and any help would be appreciated!

In a repeat of Millikan's experiment, the following values of charge on the oil drops were obtained. The unit used for charge was not the coulomb, but an older unit called the franklin.
Charge(franklin): 9.59x10^-10, 2.40x10^-9, 4.32x10^-9, 2.88x10^-9, 3.36x10^-9
Then it says I must use the data to deduce the electronic charge in franklin and to calculate the value of 1 franklin in C.

Apparently the answer is e=4.8x10^-10 franklin and 1 franklin = 3.3x10^-10 C

Any help?
The basis of the Millikan drop experiment is that the charge on the oil drops is some integer multiple of the electronic charge. So, you need to find the largest quantity of charge which divides the charge on all droplets into integers. Once you have done that, you can work out the number of coulombs in a franklin by dividing the value you got by the electronic charge in coulombs (which you have to look up).
Reply 2
Ahhhh ok, thanks!

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