A manufacturer of recordable DVDs is concerned about the quality of a recent production run. It ships a complete batch of DVDs to the same retailer to monitor quality. In a recent batch, a retailer reported one defective disc. The firm’s management believes that 1 percent of its discs do not meet its quality specifications. Of these, it is convinced that 90 percent are identified and removed prior to shipping.

If inspection is on a per-batch basis, what is the size of the questionable batch?