Answer:
20.14
Step-by-step explanation:
Given that the consumption rate of electricity, in kW/h has increased, on average, at 3.5% per year.
So if initial consumption is C after one year it would be
[tex](1+0.035)C[/tex] and after 2 years [tex](1+0.035)^2C[/tex]
and so on
In general after n years
[tex]C(n) = 1.035^n C\\[/tex]
When C(n) is twice C we have
[tex]2=1.035^n\\log 2= n log 1.035\\n = 20.14[/tex]
Between 20 and 21 years
Hence The electric utities will need to double their generating capacity in about ___20.14__ years.
