Answer:
Function for given situation is : 
Value of computer after 4 years = $720.3.
Step-by-step explanation:
Given that the value of a $3000 computer decreases about 30% each year. Now we need to write a function for the computers value V(t). then we need to find about how much will the computer be worth in 4 years.
It clearly says that value decreases so that means function represents decay.
For decay we use formula:

where P=initial value = $3000,
r= rate of decrease =30% = 0.30
t= number of years
A=V(t) = future value
so the required function is 
or 
Now plug t=4 years to get the value of computer after 4 years.


Hence final answer is $720.3.
Answer:
x= - 1/35. I'm pretty sure this is right.
Answer: $5
Step-by-step explanation: 4 children divided by 20 equals 5
Answer:
$27.2
Step-by-step explanation:
A cake that costs $32 is on sale for 15% off and there are no taxes. Explain why the expression (0.85).32 represents the final price of the cake in dollars.
This is explained in the calculation below
= A cake that costs $32 is on sale for 15% off
The amount off the cake is calculated as
= 15% of $32
= 15/100 × 32
= $4.8
The amount he is paying for the cake =>$32 - $4.8
= $27.2
The above expression is obtained as
(0.85).32
= (100% - 15%) × 32
=( 1 - 0.15) × 32
= 0.85 × 32
= $27.2
The final price of the cake = $27.2