SOLR boost documents based on distance and age -

here structure of solr document

   <doc>      <str name="latlong">52.401790,4.936660</str>      <date name="dateofbirth">1993-12-09t00:00:00z</date>    </doc> 

would search document's based on following weighted criteria..

• distance 0-10miles weight 40
• distance 10miles , above weight 20
• age 0-20years weight 20
• age 20years , above weight 10

any ideas on best ways build solr queries this?