Chapter 2 - The Key Principles of Economics - Exercises - 2.5 The Real-Nominal Principle - Page 47: 5.9a

$stable\ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \$4000\ \ \ \ \ 5\ months$ $25\% inflation\ \ \ \ \ \ \ \$5000\ \ \ \ \ 4\ months$ $50\% deflation\ \ \ \ \ \ \ \$2000\ \ \ \ \ 10\ months$

$20000\div4000=5$ $4000+(4000\times25\%)=4000+1000=5000$ $20000\div5000=4$ $4000-(4000\times50\%)=4000-2000=2000$ $20000\div2000=10$