Answer
a. $f'(x)=0.012x^2-0.122x+0.299$ dollars per year is the rate of change in the average charge to non-account holders who use an ATM, where x is the number of years after 1998, data from 1998 and 2008.
b. $2.13
c. 0.17 dollars per year
Work Step by Step
a. You tade the derivative of the original function by using the derivative rule. Take the exponent, multiply it by the number in front, then subtract one from the exponent. which gives the rate of change in surcharges for non-account holders who use an ATM.
b. To find the Estimate for the transaction fee in 2011 you just plug 13 into the original function.
c. To find the rate of change in 2009 we just need to plug 11 into the derivative function.
