买2瓶白酒和12瓶啤酒共用4元,已知1瓶白酒以8瓶啤酒的价钱相等,1瓶白酒和1瓶啤酒共需___元

问题描述:

买2瓶白酒和12瓶啤酒共用4元,已知1瓶白酒以8瓶啤酒的价钱相等,1瓶白酒和1瓶啤酒共需___元

4/(2*8+12)*(1+8)=9/7元