Problem: In 1970, Lyle bought a hand calculator for $200. The calculator was more accurate in its four functions of addition, subtraction, multiplication, and division than was Lyle's $35 slide rule. In 1990, Lyle could not buy a calculator, which could only perform four functions. The simplest calculator he could fine cost $5, and was much superior to his 1970 calculator. The CPI in 1970 was 100, and in 1990 it was 250.
Required:
Question 1: Based on the CPI, what was the value of the 1990 calculator in 1970 dollars?
Question 2: By how much had the price of the calculator fallen in real terms from 1970 to 1990?
Question 3: What problems in the use of the consumer price index as a measure of the cost of living does the above illustrate?