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:
y=5/3 is the only real solution
Step-by-step explanation:
Solve for y over the real numbers:
11 y^2 - 19 y - 10 = -4 y^2
Add 4 y^2 to both sides:
15 y^2 - 19 y - 10 = 0
The left hand side factors into a product with two terms:
(3 y - 5) (5 y + 2) = 0
Split into two equations:
3 y - 5 = 0 or 5 y + 2 = 0
Add 5 to both sides:
3 y = 5 or 5 y + 2 = 0
Divide both sides by 3:
y = 5/3 or 5 y + 2 = 0
Subtract 2 from both sides:
y = 5/3 or 5 y = -2
Divide both sides by 5:
Answer: |
| y = 5/3 or y = -2/5
Answer:
1.860 to 4sf
Step-by-step explanation:
Answer:
1/2 and 7/8
Step-by-step explanation:
Answer: Iron, a solid at room temperature, becomes a liquid at 2800 degrees Fahrenheit (really, REALLY hot) and a gas at 5182 degrees Fahrenheit (about half the temperature of the sun). When things are hot, the molecules and atoms move around more and faster, and when they are cold they are slower.
Step-by-step explanation:
