The bc utility
bc is an arbitrary precision numeric processing language, which can be used to compute simple arithmetic from the command line.
Interesting article on bc. Online manual is available here.
Note: The following examples, were taking from a Solaris 10 system
To generate decimal values:
Note: scale specifies how many digits to the right of the decimal point. The following demonstrates, 2 digits after decimal point:
# echo "scale=2; 701664/1052624" | bc
.66
To use the result of the previous calculation, automatically:
Note: use the (.) operator
# bc
2*2
4
.*4
16