For own interest, I extend a markdown rule using Jekyll.

Grammar

If a circle has a radius of {c-r} (20)cm, its circumference would be {c-c} (#c-r * 6.28)cm and its area would be {c-s} (#c-r * #c-r * 3.14)cm².

Note: For demostrating the grammer I have to add a space between ‘}’ and ‘(’.
There should be no space between ‘}’ and ‘(’.

Quick Show

If a circle has a radius of {c-r}(20)cm, its circumference would be {c-c}(#c-r * 6.28)cm and its area would be {c-s}(#c-r * #c-r * 3.14)cm².