Dropdown facility in product for different weight

[Tricops Corporation]

I want to know is there any method that a dropdown is shown for the different weight of the product at user side. Here my site is hexkart.com  . This is an online fruit and vegetable online store. I want to show the different price for the different weight of the same product.
For example like Potato 1 kg price is 20 and for 500gm price is 11 then. I want to select it from dropdown.

[llegrand]

Yes,  they are called options - here is the doc link about it.
http://http://www.abantecart.com/ecommerce-documentation/admin-user-manual/catalog-menu/products#Options%20Tab

See this example on the demo cart:

http://demo.abantecart.com/index.php?rt=product/product&path=49_50&product_id=64