Answer:
Using the estimate:
The car has to go for 1,200 miles but it consumes a gallon of gasoline for every 30 miles. The number of gallons it will need is therefore:
= 1,200 / 30
= 40 gallons
Each gallon costs $3.00 so the total cost is:
= 40 * 3
= $120
Without using the estimate:
The car has to go for 1,211 miles but it consumes a gallon of gasoline for every 29 miles. The number of gallons it will need is therefore:
= 1,211 / 29
= 41.76 gallons
Each gallon costs $3.40 so the total cost is:
= 41.76 * 3.40
= $141.98
<em>Using the estimate provides a lower cost of gasoline for the trip. </em>
Answer:
f^-1 (x) = -21x + 7 is your answer
