You can define 10 Grid RowDefinitions and set Grid.Row=0 Grid.RowsPan=3 on the Scheduler and Grid.Row=3 and Grid.RowSpan=7 on the TabControl . This way the two controls will stretch in areas with a fixed ration 3:7. You can examine the described approach in the attached solution. Please let us know if it satisfies you or not.
the Telerik team
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