Answer: She started with $160.
It will take 6 weeks before she has less than half of what she originally invested.
Step-by-step explanation:
If her money is decreasing in value by 11% each week, it means that the rate at which it is decreasing is exponential.
We would apply the formula for exponential decay which is expressed as
A = P(1 - r)^t
Where
A represents the value of the investment after t weeks.
t represents the number of weeks.
P represents the initial value of the investment.
r represents rate of depreciation.
From the information given,
A = $142.40
r = 11% = 11/100 = 0.11
t = 1
Therefore
142.40 = P(1 - 0.11)^1
142.40 = P(0.89)
P = 142.4/0.89
P = 160
For her to have half of what she invested originally, then
80 = 160(0.89)^t
80/160 = (0.89)^t
0.5 = (0.89)^t
Taking log of both sides to base 10
Log 0.5 = log0.89^t = tlog0.89
- 0.3010 = - 0.051t
t = - 0.3010/- 0.051
t = 5.9
Approximately 6 weeks
Answer:
C
Step-by-step explanation:
4232 divided by 18 equals 235.1
Answer : A {-8}
-4 = b/2
-4 *2 = b
-8 = b
Answer:
g(0) > f(0)
Step-by-step explanation:
Evaluate the functions at the point of interest: x=0.
g(0) = 20·1.5^0 = 20·1 = 20
f(0) = -40 . . . . from the table
Since 20 > -40, we conclude ...
g(0) > f(0)