For easier reading of long, multi-digit numbers, 'or ' is inserted for each group of three digits e.g. 10 thousand will be displayed as 10,000 | To input two zeros by pressing the key once e.g. to input 100, (1) (00) | The calculator powers off automatically after approximately 7 minutes to save energy and prolong battery life | Change the result of calculation to positive or negative value | Recalls the value of the previous equation | To calculate certain percentage of a number e.g. 100 + 10% gives you 110. Great function for calculating before or after tax amount of a certain item | Determine the cost price for a certain margin, e.g. Cost price for 30% margin when the selling price is set at $500 - input selling price (number) (SELL) input margin (number) (MGN) (FIND) (COST), number displayed will be the cost price. Great for small business owners to calculate and determine selling price.