It takes Lynn 4 hours to drive to her grandmothers house she. has already driven 2 1/2 Hours.Which of the following equations can be used to find the amount of time she has left to drive

Let the total number of hours Lynn would drive to her grandmother house be 4
She has already driven 2 1/2 hours
Let x be the remaining hours
[tex]\begin{gathered} \text{ Remaining hours + Hours driven already = total hours } \\ \text{ Remaining hours = x} \\ \text{ Hours driven = x} \\ \text{Total hours = 4} \\ x\text{ + 2}\frac{1}{2}\text{ = 4} \end{gathered}[/tex][tex]\begin{gathered} To\text{ calculate how many hours left to drive} \\ \text{Firstly, convert the mixed fraction to an improper fraction} \\ 2\frac{1}{2}\text{ = }\frac{2\text{ x 2 + 1}}{2} \\ =\text{ }\frac{5}{2} \\ \text{Hence, the equation becomes} \\ x\text{ + }\frac{5}{2}\text{ = 4} \\ x\text{ = 4 - }\frac{5}{2} \\ \text{Common denominator is 2} \\ x\text{ = }\frac{2\text{ x 4 - 5}}{2} \\ x\text{ = }\frac{8\text{ - 5}}{2} \\ =\text{ }\frac{3}{2} \\ =\text{ 1}\frac{1}{2} \end{gathered}[/tex]She has 1 1/2 hours left to drive