Unusual problem

I have an unusual problem. I am trying to create an estimate of a population mean knowing only two things:

1) The scores of several contestants relative to each other
2) the probability density functions of each of these contestants

What would be the best way to go about this?

For example seven people are drawn from the same population and take an IQ test. The pdf for anyone sampled is normally distributed with mean 100 and sd 15.

If the scores of each contestant were as follows, what would be the best way to get the most accurate estimate of A's score:

A: got A's score
B: got A's score minus 10
C: got A's score minus 15
D: got A's score minus 30
E:got A's score minus 35
F:got A's score minus 35
G: got A's score minus 40