Question

Suppose you deposit $2000 in a bank account that has a doubling time of 19 years. To the nearest $100, what will your balance be after 5 years?

Answer 1

start with 2000
it takes 19 yrs to get another 2000
divide 2000 by 19 to get amount earned per 1 year =$105.26
multiply $105.26 by 5 yrs = $526.32
rounded to nearest 100 = $500

Answer 2

$2500

Explanation:

The amount of money will double from $2000 to $4000 every 19 years. Therefore we can determine the amount of money added to $2000 by dividing the amount of money in 19 years by 19:

`=2000/19=105.26`

The amount will increase by $105.26 per year. Therefore, for 5 years we multiply this amount by five:

`=5\cdot{105.26}=526.32=500`

The balance after 5 years will be $2500