You can use the OnClientValueChanged event (http://www.telerik.com/help/aspnet-ajax/slider-client-side-onclientvaluechanged.html) to:
- traverse the HTML to get the parent cell (each control offers a get_element() method that will return its HTML wrapper, so you can traverse the nodes hierarchy)
- get the textbox controls inside (elem.control is this reference where elem is the HTML element that wraps the textbox)
- use their client-side API (http://www.telerik.com/help/aspnet-ajax/input-client-side-radnumerictextbox.html) to change their values
You can inspect the rendered HTML to see what classes and elements are used to build your jQuery selectors.
Check out the Telerik Platform - the only platform that combines a rich set of UI tools with powerful cloud services to develop web, hybrid and native mobile apps.