Calculating period  Mass on a spring
Hello all, I am writing a lab report for physics and I am wondering if my calculations are valid. I am to calculate the period of a mass on a spring and then to find out how the changing of that mass affects the period. The original formula I am meant to use is 'T = n/t', the number of vibrations (oscillations in this case) divided by the time (seconds). Something went wrong during the experiment and so now when I put my results into the above formula, I do not get any sort of correlation.
So I then turned to the formula for calculating the period for a mass on a spring  'T = 2pi * square root of m/k'. Now I thought, if I want to solve for K, I can simply take the average of the 'n' and 't' and do the following 
7.3335/3.74 = 6.28 * square root of 50/k
Where 7.3335 is the average oscillations and 3.74 is the average time. Now my question is, is this allowed? The reason why I thought this was allowed was that T = n/t, so why shouldn't n/t = 2pi * square root of m/k, as they are different ways to find the same thing? Correct? or am I wrong?
Thank you!
