You can perform simple aritmetic operations on the Linux shell command line, without using any external program.

use the command expr

These are the aritmetic operations.

  • Add
  • expr 1 + 2

  • Substract
  • expr 2 - 1

  • Multiply
  • expr 2 \* 1

  • Divide
  • expr 2 / 1

  • Reminder of a divition
  • expr 20 % 3

Note that for multiplication we escape the * character, with the back slash, and that the % operand gives as the reminder of a divition, also the divition is only giving as the Integer