hello
Noslo spent 475minutes on call for that month, but we already know the price on the first 350 minutes
if Noslo is charged $39.95 for 350 minutes, we can subtract $39.95 from $108.70 and also 475 from 350 to know the cost and number of minutes respectively.
the number of minutes is
[tex]475-350=125\text{ minutes}[/tex]the cost of the minutes is
[tex]108.70-39.95=68.75[/tex]so, what this information implies is thar Noslo was charged $68.75 for 125 minutes.
we can easily find how much he's charged per minute from here.
let's make x represent that
[tex]\begin{gathered} 125=68.75 \\ 1=x \\ \text{cross multiply both sides} \\ x\times125=68.75 \\ 125x=68.75 \\ \text{divide both sides by the coefficient of x} \\ \frac{125x}{125}=\frac{68.75}{125} \\ x=0.55 \end{gathered}[/tex]from the calculations above, Nsolo was charged $0.55 per minute