Question 147825
Solve the cost equation for those two dollar amounts to find the corresponding times.
1.{{{0.25(t[1]-600)+ 55.95=105.95}}}
{{{0.25(t[1]-600)=50}}}
{{{t[1]-600=200}}}
{{{t[1]=800}}}
2.{{{0.25(t[2]-600)+ 55.95=119.70}}}
{{{0.25(t[2]-600)=63.75}}}
{{{t[2]-600=255}}}
{{{t[2]=855}}}
For the cost to be between $105.95 and $119.70 the telephoning time must be between {{{highlight(800)}}} minutes and {{{highlight(855)}}} minutes.