Mary enjoys classical CDs and travel books and spends a75 a month on them. The following table shows the utility she gets from each good:
Quantity Utility from classical CDs Utility from travel books
1 90 120
2 110 136
3 126 148
4 138 152
5 146 154
a Draw graphs showing Mary's utility from classical CDs and from travel books.
b Compare the two utility graphs. Can you say anything about Mary's preferences?
c Draw graphs that show Mary's marginal utility from classical CDs and from travel books.
d What do the two marginal utility graphs tell you about Mary's preferences?
e If a classical CD and a travel book cost a15 each, how does Mary spend the a75 a month?