You could customize the text in the tooltip
via its properties. For your scenario you need the series
variable in the template. For example:
"#= series.name # , value: #= value # %"
For convenience, I prepared a small jsFiddle example
which illustrates such approach in action.
More detailed information about the Kendo UI Chart is available in our online documentation
the Telerik team
Check out the successor of Telerik MVC Extensions - Kendo UI for ASP.NET MVC - and deem it for new ASP.NET MVC development.