还有一道GMAT数学题
Atacertainfoodstand,thepriceofeachappleis¢40andthepriceofeachorangeis¢60.Maryselectsatotalof10applesandorangesfromthefoodstand,andtheaverage(arithmeticmean)priceofthe10piecesoffruitis¢56.HowmanyorangesmustMaryputbacksothattheaveragepriceofthepiecesoffruitthatshekeepsis¢52?
A.1
B.2
C.3
D.4
E.5
(为什么不选d,4个orange,6个apple,平均价格刚好是52呀)