Cost of living again. In Exercise 43, we examined the Worldwide Cost of Living Survey cost of living index. Now we use the Restaurant Price Index to predict total cost of living. Here are the results:

R-squared = 90%

s = 6.95 with 511 - 2 = 509 degrees of freedom Predictor Estimate Std Error t-Ratio P-Value Intercept 18.14 0.75 24.3 6.0001 Restaurant Price 0.80 0.01 69.1 6.0001

a) How do you interpret the coefficient of Restaurant price?

b) The R2 of this regression is 90%, and the R2 of the regression from Exercise 43 was 91%. How is it possible that both variables explain almost 90% of the variation in total cost of living?