Download the latest version in tar/zip from tomcat website and extract it.
open the [tomcat extract directory]/bin/catalina.sh in editer and change the JAVA_HOME and JRE_HOME path with your installed java's jdk and jre path.
move the tomcat directory to /usr/share/[tomcat7] by following command
sudo mv [tomcat extract directory]/ /usr/share/tomcat7
now run the catalina.sh by folowing command