an online shopping retailer is experimenting with two different versions of its website. the webpage randomly loads one of the two versions to every new request for the webpage. version a was viewed by 3,250 customers from whom 1,320 ending up buying a product of the website. version b was viewed by 2,870 customers from whom 1,250 purchased a product. the retailer is asking you whether any of the two version is associated with higher sales conversion (i.e., higher chance of a customer purchasing). what would you answer to them?