Let's say the APR is 5%. That means you get 5% of your balance back every year. The $100 balance would get $5 back, the $500 balance would get $25 back, and the $1000 balance would get $50 back. Therefore, all of the balances would take the same amount of time to double, and it would take all of them 20 years.
$5*20 years=$100
$25*20 years=$500
$50*20 years=$1000
Answer:
A. 6.5
Step-by-step explanation:
First we find the average 
of the 9 data:
Where n is the data number, that in this case is 9.
The formula of the standard deviation 
is:
We replace the data and find the value of the standard deviation:
We approximate the number and the solution is 6,5
Notice that 45 hours is 3 times the half-life of 15 hours.
After the first 15 hours, 450 g decays to half this amount, 225 g.
After the next 15 (total 30), 225 g decays to 112.5 g.
After the next 15 (total 45), 112.5 g decays to 56.25 g.
the difference of 5 times the cube of x cubed and the quotient of 4 times x and 3
5*x^3 - (4x/3)
