Title:
Step-by-step explanation:
As per October 2009, the world's estimated population is 6.8 billion.
The population growth rate is 0.07 billion per year.
Hence, in x year, the population will increase 0.07x billion.
We need to find the time, after which the population will be 9.5 billion.
If we take x as the number of year that will be required, then we can represent it as
[tex]6.8 + 0.07x = 9.5\\0.07x = 2.7\\x = 38 + \frac{4}{7}[/tex].