Question

A city manager believes more charging stations are needed to meet future electric vehicle needs in public parking locations. A previous study found that 64%of the available charging stations were in use during randomly selected business hours. A new study finds 423 charging stations in use out of 625 randomlyselected charging station checks by parking officials.Does this provide evidence that the need for electric vehicle charging stations has increased?

Answer 1

625 stations represent 100%. We need to find what percentage represents 423 stations. To do it, we can use the next proportion,

`\frac{625\text{ stations}}{423\text{ stations}}=\frac{100\text{ \%}}{x\text{ \%}}`

Solving for x,

`\begin{gathered} 625\cdot x=100\cdot423 \\ x=(42300)/(625) \\ x=67.68\text{ \%} \end{gathered}`

Given that 67.68% is greater than the previous 64%, then this provides evidence that the need for electric vehicle charging stations has increased