Question

An internet cafe charges a fixed amount per minute to use the internet. The cost of using the internet in dollars is, y = 3/4x. If x is the number of minutes spent on the internet, how many minutes will $6 buy?3 minutes4 minutes6 minutes8 minutes

Answer 1

8 minutes

Step-by-step explanation

We know that the cost of using the internet in dollars is given by,

`y=(3)/(4)x`

Where x is the number of minutes spent on the internet.

In this problem, we have to find how many minutes will 6 dollars buy. In other words, we have to find x for y = 6. To solve the given equation for x, we have to multiply both sides by 4,

`\begin{gathered} 4y=4\cdot(3)/(4)x \\ \\ 4y=3x \end{gathered}`

And divide both sides by 3,

`\begin{gathered} (4y)/(3)=(3x)/(3) \\ \\ (4y)/(3)=x \end{gathered}`

So, for y = 6, x is,

`x=(4\cdot6)/(3)=(24)/(3)=8`

Hence, $6 will buy 8 minutes.