微经书上有这样一题``` 从论坛里下的答案
Orange juice and apple juice are known to be perfectsubstitutes.
Draw the appropriate price-consumption (for a variable price of orange juice) and income-consumptioncurves.
We know that theindifference curves for perfect substitutes will be straight lines.
In this case, the consumer will alwayspurchase the cheaper of the two goods.
If the price of orange juice is less than that of apple juice, theconsumer will purchase only orange juice and the price consumption curve willbe on the “orange juice axis” of the graph.
If apple juice is cheaper, the consumer will purchase only apple juiceand the price consumption curve will be on the “apple juice axis.”
If the two goods have the same price, theconsumer will be indifferent between the two; the price consumption curve willcoincide with the indifference curve.
See Figure 4.5.a.i.
Assuming thatthe price of orange juice is less than the price of apple juice, the consumerwill maximize her utility by consuming only orange juice.
As the level of income varies, only theamount of orange juice varies.
Thus, theincome consumption curve will be the “orange juice axis” in Figure 4.5.a.ii.
感觉有点不对``` 只有橙汁的price是variable那么为什么会有苹果汁轴上的那一段呢?应该只能有E点阿?
还有income-consumption curves 怎么画阿? 不应该是所有收入下的budget line嘛?而答案为什么是那样呢?