run time Indian rupees convert into dollar in c# .net

Question

how to convert  rupees  in to dollar...

 bind grid view run time product price save in Indian rupees but i want to show this price into dollar

 

i insert another table dollar current price.

 

 

i want when grid view bind than all price divide with current dollar price  for example :

 

i insert 500 rs or 200, 300,  500/ 60= 8.33$

when grid bind show price in dollar like  8.33$

when we change dollar price 62 than all price divide this current price than show like:  8.06$