**echo ’25+7′ | bc **– addition

**echo ’25-7′ | bc **– subtraction

**echo ’25*7′ | bc **– multiplication

**scale **– the scale variable tells how many decimal places to take your answer. The default is 0, unless using -l, in which case the default is 20.

**echo ‘scale=5;25/7’ | bc ** division

3.57142

**echo ‘scale=10;sqrt(7)’ | bc **square root

2.6457513110

**bc -q **interactive mode