i have shopping cart page when i click update cart button then qty and amount values are not multiply i don't know why it is not working?

i have shopping cart page when i click update cart button then qty and
amount values are not multiply i don't know why it is not working?

References

Reference NO 1

http://www.ecomdev.org/2012/12/12/magento-checkout-shopping-cart-flow.html

Reference NO 2

http://www.prestashop.com/forums/index.php?/topic/230544-use-ajax-cart-script-to-product-page/

Reference NO 3

http://wordpress.org/support/topic/wp-e-commerce-checkout-problem

Reference NO 4

https://www.paypal.com/cgi-bin/webscr?cmd=_shoppingcart-intro-outside

Reference NO 5

http://www.drupalcommerce.org/user-guide/cart

Reference NO 6

http://forums.oscommerce.com/topic/392931-update-price-automatically-after-selecting-product-attribute/

Reference NO 7

https://github.com/wojodesign/simplecart-js

Reference NO 8

http://www.coolcart.net/PM/help/tags.aspx