When using the number selector in the new Operations Dashboard for ArcGIS browser, the slider tool does not function to filter any features in the map display.
When configuring a number selector to work with other elements in the dashboard, you also need to set the target and action you want to happen. In the config for each selector, there is a tab for Selector (setting the display, range, filter, etc) and the Actions tab (when selection changes, do this...)
See these help topics for more information:
http://doc.arcgis.com/en/operations-dashboard/help/selectors.htm
http://doc.arcgis.com/en/operations-dashboard/help/actions.htm