The population Pa of insect A after t years is given by the equation
Pa = 1.3(1-0.038)^t
while the population Pb of insect B after t years is
Pb = 2.1(1-0.046)^t
We equate the above expressions to find the number of years t it will take the two populations to be equal:
Pa = Pb
1.3(1-0.038)^t = 2.1(1-0.046)^t
1.3(0.962)^t = 2.1(0.954)^t
These are the equations that can be used to determine how long it will be before the populations of the two species are equal.
We can now solve for t:
(0.962)^t / (0.954)^t = 2.1/1.3
(0.962/0.954)^t = 2.1/1.3
After taking the log of both sides of our equation, number of years t is
t = log (2.1/1.3) / log (0.962/0.954)
t = 57 years
Therefore, it will take 57 years for the population of insect A to equal the population of insect B.
Answer:
Step-by-step explanation:
common ratio=18/-3=-108/18=-6, a=-3
sn=a(r^n-1)(r-1)
sn=-3((-6)^n-1)(-6-1)
sn=-3(-6)^8-1)/(-7)
s8=-3(1679615)/(-7)
s8=719836
Answer:
22
Step-by-step explanation:
I did it on math class
Step-by-step explanation:
-(-3x-5)=7x
3x+5=7x
4x=5
x=5/4