gcalctool software package provides GNOME desktop calculator, you can install in your Ubuntu 12.04 LTS (Precise Pangolin) by running the commands given below on the terminal,
$ sudo apt-get update $ sudo apt-get install gcalctool
gcalctool is installed in your system.
Make ensure the gcalctool package were installed using the commands given below,
$ sudo dpkg-query -l | grep gcalctool *
You will get with gcalctool package name, version, architecture and description in a table
| Distro | Ubuntu 12 04 lts precise pangolin |
| Section | Mathematics |
| Package | gcalctool |
| Version | 6.4.1.1-0ubuntu2 |
| Description | GNOME desktop calculator |
| Sub Section | Math |