You can do it following these steps:

1. Define a case field within the Summary Statistics tool (some sort of ID field).
2. Use Join Field tool to join the summary table back to your original layer
3. Use Select Layer by Attribute tool to define your selection based on your expression

Hope that helps.

You can do it following these steps:

1. Define a case field within the Summary Statistics tool (some sort of ID field).
2. Use Join Field tool to join the summary table (by case field) back to your original layer
3. Use Feature Class to Feature Class tool to export out a new shapefile which includes the new statistic fields
4. Use Select Layer by Attribute tool to define your selection based on your expression

Hope that helps.