Question

ÔÆÄÏijÊß²ËÓÐÏÞ¹«Ë¾Ò»ÄêËļ¾¶¼ÓдóÁ¿ÐÂÏÊÊß²ËÏúÍùÈ«¹ú¸÷µØ£¬ÒѳÉΪÎÒÊ¡¾­¼Ã·¢Õ¹µÄÖØÒªÏîÄ¿¡£½üÄêÀ´ËüµÄÊ߲˲úÖµ²»¶ÏÔö¼Ó£¬2009ÄêÊ߲˵IJúÖµÊÇ640ÍòÔª£¬2011Äê²úÖµ´ïµ½1000ÍòÔª¡£
СÌâ1:ÕâÁ½ÄêµÄÊ߲˲úÖµÔö³¤ÂÊÏàͬ£¬ÇóÊ߲˲úÖµµÄÄêƽ¾ùÔö³¤ÂÊÊǶàÉÙ£¿
СÌâ2:Èô2012ÄêÊ߲˲úÖµ¼ÌÐøÎȲ½Ôö³¤£¨¼´ÄêÔö³¤ÂÊÓëÇ°Á½ÄêµÄÄêÔö³¤ÂÊÏàͬ£©£¬ÄÇôÇëÄã¹À¼Æ2012Äê¸Ã¹«Ë¾µÄÊ߲˲úÖµ½«´ïµ½¶àÉÙÍòÔª£¿

Answer 1

СÌâ1:ÉèÊ߲˲úÖµµÄÄêƽ¾ùÔö³¤ÂÊΪx£¬¡­¡­¡­¡­¡­¡­£¨1·Ö£©
ÒÀÌâÒâµÃ  640£¨1£«x£©²£½1000£¬½âµÃ£º¡­¡­¡­¡­¡­¡­£¨3·Ö£©
x₁=£¬      x₂=-£¨²»ºÏÌâÒ⣬ÉáÈ¥£©
´ðÂÔ¡£               
СÌâ2:1000£¨1£«25%£©£½1250£¨ÍòÔª£©
´ðÂÔ¡£   

·ÖÎö£º£¨1£©ÉèÊ߲˲úÖµµÄÄêƽ¾ùÔö³¤ÂÊΪx£¬¸ù¾Ý2009ÄêÊ߲˵IJúÖµ¡Á£¨1+Äêƽ¾ùÔö³¤ÂÊ£©²=2010Äê²úÖµ£¬Áз½³Ì½â´ð¼´¿É£®
£¨2£©ÀûÓã¨1£©µÄ½áÂÛ¼´¿É½â´ð£®
½â´ð£º½â£º£¨1£©ÉèÉè³ö2010Äê¡¢2011ÄêÊ߲˲úÖµµÄÄêƽ¾ùÔö³¤ÂÊÊÇx£¬ÒÀÌâÒâÁз½³ÌµÃ£¬
640£¨1+x£©²=1000£¬
½âµÃx₁=£¬x₂=-£¨²»ºÏÌâÒ⣬ÉáÈ¥£©
´ð£ºÊ߲˲úÖµµÄÄêƽ¾ùÔö³¤ÂÊΪ 25%£»
£¨2£©1000£¨1+25%£©=1250£¨ÍòÔª£©£¬
´ð£º2012Äê¸Ã¹«Ë¾µÄÊ߲˲úÖµ½«´ïµ½1250ÍòÔª£®