September MDX Puzzle

The FoodMart 2000 database includes a virtual cube called Trained Cube, with a data-mined dimension called Customer Pattern. This dimension is based on a decision-tree model called Customer Pattern Discovery. To discover how well this model predicts a particular member card, write an MDX query that returns the percent of customers identified by the [Customer Pattern].[All].[Customers.Name.Yearly Income = $10K - $30K] dimension member that have a Normal Member Card. (Hint: The answer should be greater than 90 percent!)