1.第一个are变成is.
2.把最后一个are去掉.
The fridge made in Germany is much more expensive than that made in China.
德国产的冰箱比中国产的要贵得多.
that是指代前面所说的fridge,前后句子平衡一致,所以made in china和made in Germany相一致.
冰箱用的是单数,而且后面指代词用的是单数的that,谓语动词应该用is,而不是are.