Answer:
$6.9
Step-by-step explanation:
If gallon of milk cost 1.12 in 1970, we can calculate the expected price in 2009 per gallon of milk using the proportion below:
2009 price/214.5 = $1.12/38.8
=>Find the expected price of 2009 by cross multiplying
38.8 × 2009 price = 1.12 × 214.5
38.8 × 2009 price = 240.24
=>Divide both sides by 38.8
2009 price = 240.24/38.8
2009 price = 6.19175258 ≈ 6.19
Expected price of gallon of milk in 2009 = $6.19