### Home > PC > Chapter 7 > Lesson 7.3.1 > Problem7-99

7-99.

Abra is saving to buy a car. She has found a very generous bank that will give her $1\%$ interest every month ($12\%$ annual interest compounded monthly). Each month Abra adds $200$ to the account. How much will Abra have saved after one year? Hint: Think of each $200$ deposit as a separate investment. The first $200$ will receive interest for $11$ months, the 2nd $20$0 deposit will receive interest for $10$ months, and so on. The 12th deposit does not get any interest.

1st month $= 200\left(1.01\right)¹¹ = 223.1336693$
2nd month $= 200\left(1.01\right)^{10} =$
3rd month $= 200\left(1.01\right)^{9} =$
4th month $= 200\left(1.01\right)^{8} =$
5th month $= 200\left(1.01\right)^{7} =$
6th month $= 200\left(1.01\right)^{6} =$
7th month $= 200\left(1.01\right)^{5} =$
8th month $= 200\left(1.01\right)^{4} =$
9th month $= 200\left(1.01\right)³ =$
10th month $= 200\left(1.01\right)² =$
11th month $= 200\left(1.01\right)¹ =$
12th month $= 200\left(1.01\right)^{0} = 200$