Home > Statistic of the Week > Archive List > Detail

<< Prev 3/25/2012 Next >>

$1.25 at The Most?

Consider the cost of one gallon of unleaded gasoline over a past series of years:

  • 1984: $1.21
  • 1985: $1.25
  • 1986: $0.92
  • 1987: $0.95
  • 1988: $0.95
  • 1989: $1.02
  • 1990: $1.16
  • 1991: $1.14
  • 1992: $1.13
  • 1993: $1.11
Question: Based on this data (and using linear or exponential fits), what would you predict is the current price of gasoline? When comparing your prediction to the actual price, be prepared to be surprised that it is much different (higher or lower?). How can you explain this?


G.G. (Clarkston Schools) sent me this note regarding these statistics: "I loved exploring the gas price problem with my PreCalculus class. We ended up leaving out the first two years, doing an exponential regression and getting a 2012 price of $2.24, in 1980 dollars. Adjusting for 2% inflation, our projected price is $4.25, which sounds pretty close to No Surprise Here! (and 3% inflation yielded a price of $5.75!) Thanks for the weekly entertainment and edification..."