2/8 is equivalent to 1/4. 1/4 + 3/4 = 1
Hope this helps!! :)
Answer: a) , where 'A' is the value of car after 't' years.
b) $12446.784
Step-by-step explanation:
Given: A new car that sells for $21,000 depreciates (decreases in value) 16% each year.
Then a function that models the value of the car will be
, where 'P' is the selling price of car, 'r' is the rate of depreciation in decimal, 't' is the time in years and 'A' is the value of car after 't' years.
Thus after substituting given value, the function becomes
To find the value after 3 years, substitute t=3 in the above function.
Hence the value of car after 3 years=$12446.784
To get started, we will use the general formula for bacteria growth/decay problems:

where:
A_{f} = Final amount
A_{i} = Initial amount
k = growth rate constant
t = time
For doubling problems, the general formula can be shortened to:

Now, we can use the shortened formula to calculate the growth rate constant of both bacteria:
Colby (1):


per hour
Jaquan (2):


per hour
Using Colby's rate constant, we can use the general formula to calculate for Colby's final amount after 1 day (24 hours).
Note: All units must be constant, so convert day to hours.


Remember that the final amount for both bacteria must be the same after 24 hours. Again, using the general formula, we can calculate the initial amount of bacteria that Jaquan needs:

Answer:
d 13
Step-by-step explanation:
Subtracting means adding the opposite.
To subtract -4, you add the opposite of -4 which is 4, so you add 4.
9 - (-4) = 9 + 4 = 13
Answer: d 13