Common Installation error.
Solution:
1. Download Oracle 11G Database.
2. Linux.x64_11gR2_Database_1of2.zip & Linux.x64_11gR2_Database_2of2.zip
3. Unzip both zipped files.
4. It will create to folders etc...database & database (2).
5.Goto to second folder etc...database (2)
6. Copy the following directories under below path.
/database (2)/stage/components/
oracle.ctx
oracle.jdk
oracle.owb.rsf
oracle.rdbms.install.seeddb
oracle.sysman.console.db
7. Paste all directories in below path.
/database/stage/components/
8. Run the installation.