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:
-4(5-x)
Step-by-step explanation:
The logarithmic expression of 4^(1/2) = 2 is 
<h3>How to rewrite the expression?</h3>
The expression is given as:
4^(1/2) = 2
Take the logarithm of both sides
log(4^(1/2)) = log(2)
Apply the change of base rule
1/2log(4) = log(2)
Divide both sides by log(4)
1/2 = log(2)/log(4)
Change the base
Rewrite as:
Hence, the logarithmic expression of 4^(1/2) = 2 is
Read more about logarithmic expression at:
brainly.com/question/24211708
#SPJ1
Answer:
12 weeks
Step-by-step explanation:
Step one:
given data
let the heights of the plants be y
and the number of weeks be x
Plant A
y=3x+8.5--------------1
Plant B
y=2.5x+14.5----------2
Required
The number of weeks taken for both plants to have the same height
,equate the two expressions above
3x+8.5=2.5x+14.5
3x-2.5x=14.5-8.5
0.5x= 6
divide both sides by 0.5
x= 6/0.5
x= 12 weeks
What you have here is the fibonacci sequence.
Each number in the sequence adds itself to the number before it.
1+1 = 2
1+2 = 3
3+2 = 5
5+3 = 8
8+5 = 13
the sequence is 0,1,1,2,3,5,8,13
