英文的數學題目...幫我解

Question

有一題......急需

題型: Work Backwards to the solution

1. A dealer sold a radio to a stranger for 89 dollars and was given a 100 dollars bill as payment. The dealer, having no change, went next door and had the butcher change the bill. The stranger departed with the change and radio. Later, and excited butcher appeared, stating that the 100 dollars bill was counterfeit. The dealer reimbursed the butcher with a legal 100 bill. How much had the dealer lost?

最好能列出算式和過程..

Answer 1

$100 + $11 + 收音機= $110 和收音機A dealer sold a radio to a stranger for 89 dollars.So, the dealer lost the radio and the $11 at this point.如此, 經銷商這時丟失了收音機和$11 。And was given a 100 dollars bill as payment. Later, and excited butcher appeared, stating that the 100 dollars bill was counterfeit.The dealer, having no change, went next door and had the butcher change the bill. The stranger departed with the change and radio.  The dealer reimbursed the butcher with a legal 100 bill. So the dealer lost the $100.Thereby, $100 + $11 + Radio = $110 and Radio如此經銷商丟失了$100 。從而, $100 + $11 + 收音機= $110 和收音機

Answer 2

$100 + $ 89 + ( $100 - $89 ) = $200

答 : $200

2006-05-23 06:35:20 補充：
樓下的燕子, 不要忘了那個買 radio 的人把dealer找給他的11 塊也拿走了, so the dealer lost $200