If the manager wants to have a margin error of 0.5% (.005), then how many items need to be cross-checked?Explain

The items for sale in many retail stores sometimes ring up at a different price at the cash register compared to the price marked on the shelf. This goes unnoticed by many consumers. But whether the mistakes are intentional or not, the retailers get checked by government inspectors (for overcharges only) and can potentially be fined for the mistakes if their error rate is high enough.