b In this function, a is the initial value and b is the multiplier.
C
c Substitute t=5 into the function.
A
a 0.85
B
b f(t)=27 000(0.85)^t
C
c About $11 980
Practice makes perfect
a The multiplier shows the percentage change expressed in decimal form. Since the car decreases in value, we can find the multiplier by subtracting the percentage expressed in decimal form from 1.
1-15/100=1-0.15=0.85
The multiplier is 0.85.
b In the function f(t)=ab^t, a represents the initial value and b is the multiplier. From the exercise we know that the initial value is a= 27 000. From Part A, we know that the multiplier is b= 0.85. Let's substitute these into the function.
f(t)= 27 000( 0.85)^t
c By substituting t=5 into the function we can determine the value of the car in 5 years.
