問題：A sole trader fixes his prices to achieve a gross profit percentage on sales revenue of 40%. All his sales are for cash. He suspects that one of his sales assistants is stealing cash from sales revenue.
　　His trading account for the month of June 20X3 is as follows:
　　                                                                                             $
　　Recorded sales revenue                                          181,600
　　Cost of sales                                                               114,000
　　Gross profit                                                                   67,600
　　Assuming that the cost of sales figure is correct, how much cash could the sales assistant have taken?
　　A. $5,040
　　B. $8,400
　　C. $22,000
　　D. It is not possible to calculate a figure from this information
　　答案：The correct answer is:$8,400
　　解析：Cost of sales = $114,000
　　Therefore sales should be = $114,000 × 100/60 = $190,000
　　Theft = $190,000 - 181,600 = $8,400