Question #5
Given:
The number of people who own computers has increased 23.2% annually since 1990
In 1990: the number of people who own computers = half a million
We will predict the number of people in 2015
We will use the following formula:

Where: (r) is the ratio of increasing = 23.2% = 0.232
And (t) the number of years after 1990
And P₀ is the initial value of the number of people
P(t) will be the number of people after (t) years
To predict the number of people in 2015
t = 2015 - 1990 = 25 years
so,

So, the answer will be:
The estimated number of people = 11.43 million