Question

At birth bens dad puts $1 in a savings account. Each year on his birthday he goves him double the amount in his account. Write a exponential equation.

How much money will he have in his account on his 18th birthday?

Answer 1

This problem Is an example of geometrica progression. The formula for the sum of geometric progression is:

S = a[(r^n)-1] / (r – 1)

Where s is the sum

a is the first term = 1

r is the common ratio = 2 ( because it doubles every year

n is the number of terms = (19) since the first term is when he was born which he still 0

s = S = 1[(2^19)-1] / (2 – 1)

s = $524,287