Answer:
a). The function is: A=20 t+400, where A=total amount of profit, and t number of years
b). Total profit=$600 after 10 years
Step-by-step explanation:
a).
The function for the total amount of profits your investment will receive after a given period is given by;
A=P+PRT
where;
A=total amount of profits
P=initial profit
R=rate of increase
T=number of years
In our case;
P=$400
R=5%=5/100=0.05
T=t
replacing;
A=400+(400×0.05×t)
A=400+20 t
A=20 t+400....equation 1
b). Substitute the value of t in equation 1 with 10 years, and solve
A=20 t+400
but;
t=10
replacing;
A=(20×10)+400
A=200+400=600
Total profit=$600 after 10 years