Answer:
55years
Explanation:
According to the given expression
FV = P +Prt
P is the initial deposit = $1000
FV is the future value = 4(1000) = $4000
r is the rate = 5.5% = 0.055
Required
Time t
Substitute the given values into the expression as shown;
FV = P +Prt
4000 = 1000 + 1000(0.055)t
4000 - 1000 = 55t
3000 = 55t
Swap
55t = 3000
t = 3000/55
t = 54.5years
t = 55years
This means it will take the deposit of $1000 55years to quadruple
I'd say the first or third one, however, I'm not too sure:)
The store with the larger numbers
We would need a sample size of 560.
We first calculate the z-score associated. with this level of confidence:
Convert 95% to a decimal: 95% = 95/100 = 0.95
Subtract from 1: 1-0.95 = 0.05
Divide by 2: 0.05/2 = 0.025
Subtract from 1: 1-0.025 = 0.975
Using a z-table (http://www.z-table.com) we see that this is associated with a z-score of 1.96.
The margin of error, ME, is given by:

We want ME to be 4%; 4% = 4/100 = 0.04. Substituting this into our equation, as well as our proportion and z-score,