Myth is often an attempt to relate spiritual truths that provide meaning in our lives. Religion will often utilize myths because to the degree that meaning is important to us humans, the desire to find comfort in stories that provide meaning can make life all the more satisfactory. Science provides a different kind of meaning in that our most cherished observational abilities are mostly satisfied by the theories which we use to explain the phenomena we observe.
A conflict occurs, however, when we try to bring the world of myth, the world of religion, and the world of science together for one cohesive explanation where nothing is seen as in conflict. So, for example, the story of Adam and Eve, must match the requirements of science which demands utter preciseness and cohesiveness with the theories of science. If this cannot be achieved, then something has to give up ground or a contradictory position(s) must be taken.
Rather than go this route, why not accept the position that each applies in the 'world' in which it is most effective? For example, myth is much more effective in the position that there are some universal truths which we should understand from the story. Religion is much more effective if we accept that it offers substantial meaning to human life and all the importance we humans place on being special and having satisfaction with regards to our past and future. Science is effective as a tool by which to understand and manipulate nature.
If you take this kind of position, you will find no need to explain Adam's life in terms of science. The story of Adam describes some universal truth about humanity, and therefore it is much more prudent to understand what those universal truths are versus trying to twist science to account for the age of any remnants remaining from him. It might make the world much more meaningful if Adam was a figure that could even by hypothetically studied by science, but then you sacrifice the observational meaning obtained by science, and this in the longrun leads to an irrational path that only harms the meaning of myth as well as the meaning found in religion.