in 1998 rachel opened an account paying 4% annual interest. Has her money doubled yet? if so when did it and if not when will it.
Is that simple or compound interest?
it does not say, i would think simple
To determine if Rachel's money has doubled, we need to calculate the time it takes for her money to double using the given 4% annual interest rate.
To find out how long it takes for an investment to double using compound interest, we can use the Rule of 72. The Rule of 72 states that you divide the number 72 by the interest rate to determine the approximate number of years it takes for an investment to double.
In this case, Rachel's interest rate is 4%. So, using the Rule of 72, we divide 72 by 4:
72 รท 4 = 18
Therefore, Rachel's money will double in approximately 18 years.
Now, let's determine if her money has already doubled. We have the information that Rachel's account was opened in 1998. To find out if her money has doubled yet, we need to add 18 years to 1998:
1998 + 18 = 2016
So, if it's currently 2016 or later, Rachel's money has already doubled. If it's still before 2016, her money has not yet doubled.
Keep in mind that this calculation assumes that Rachel has not withdrawn any money from the account and that the interest is compounded annually.