In 2003, Sammy received $10,000 from her grandmother. Her parents invested all of the money in account that pays interest annually and by 2015, the amount will have grown to $16,900...Write an exponential function to model this growth...Then assume the money continue to grows at the same rate. What would be the balance in 2025?

Question

anonymous · Answer

Well first how many years are between 2003 and 2015? 12
So x stands for the amount earned per year by leaving the money in the account.
12x + 10,000 = 16,900
         -10,000   -10,000
   12x = 6,900
 ÷ 12     ÷  12
      x =   575
So Sammy gets 575 dollars a year. 
So to plug that into the second problem it would be;
2025 - 2003 = 22
So, 22 (575) = 10,000 = z
      12650 +10,000  = z
              22650 = z

Am I clear enough?