I was wondering how I could find the inductor mean current?
If all you know about a waveform is its peak-peak amplitude, no, that's not enough to determine its mean. 

If you know the wave-shape of a periodic signal with period \$T\$, then in general you can the mean from

$$\bar{x}=\frac{1}{T}\int_{t_0}^{t_0+T}x(t)dt.$$

If the wave-shape is known to be a triangle wave (for example, in the inductor of a buck regulator), then the mean value is simply the average of the minimum and maximum values the signal takes in each cycle. But that's a special case that you could work out by using the integral formula.