What is the relationship between the median and the mean?
Hozo et al. (2005) show that for a variable with minimum, min and maximum, max its mean is approximately equal to $$\frac{\mbox{min+median+max}}{4}$$. They suggest using this for small samples < 25.
Reference
Hozo, S-P, Djulbegovic, B and Hozo, I (2005). [attachment:meanmedian.pdf Estimating the mean and variance from the median, range, and the size of a sample.] BMC Medical Research Methodology 5 13. doi:10.1186/1471-2288-5-13. See also the link [http://www.biomedcentral.com/1471-2288/5/13 here.]