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:
The answer is spread from 1 to 6! This is because the dots are spread through numbers 1-6 and there are no gaps.
That would be B, C and E.
A and D could be a rhombus.
Answer:
x = 4, y = 2
Step-by-step explanation:
Start by multiplying the first equation by 2:
2x + 2y = 12 --> 4x + 4y = 24
Subtract the second from the first:
4x + 4y = 24
- 5x + 4y = 28
4x - 5x = -x
4y = 4y = 0
24 - 28 = -4
so you end with -x + 0 = -4
Solve for x to get x = 4
Plug x = 4 back into 2x + 2y = 12 to find y.
2(4) + 2y = 12
8 + 2y = 12
2y = 4
y = 2
18). 16:80 is the ratio but in simplest form is; 5:0
19). 36:54 is the ratio but in simplest form is; 2:3
20). 12:24 is the ratio but in simplest form is; 1:2
hope that helps:D
