The Economic Way of Thinking 13th Edition by David Prychitko, Peter Boettke, Paul Heyne

Exercise 23

"Save it," somebody says. "Don't sell it. It's not worth much now, but in 20 years it will probably be worth five times as much." Should you save it or sell it? What will $1 now be worth in 20 years if invested at the rate of interest currently obtainable from relatively risk-free loans?