PART I - Chapter 1

After the price change, new books cost $88, used books cost $52.50, and he has an income of $440. If he spends all of his income on new books, he can still afford to buy 5 new books, but he can now afford to buy 8.4 used books if he buys only used books. The new budget line is 88N + 52.50U = 440. ................
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