Correct answer is D.
During the first 150 miles, she drove 150 miles at a speed of x<span> miles per hour, so her time was
</span><span>
</span>where
<span>is the time she spent driving the first 150 miles.
</span>
On the second half of the trip, she drove at <span>1.25x</span> miles per hour. There, the equation would be
where
is the time she spent driving the second 150 miles.
Solve both of those equations for the t<span> variables, then add them together. Your answer will be
</span>
During the first 150 miles, she drove 150 miles at a speed of x<span> miles per hour, so her time was
</span><span>
</span>where
</span>
On the second half of the trip, she drove at <span>1.25x</span> miles per hour. There, the equation would be
where
Solve both of those equations for the t<span> variables, then add them together. Your answer will be
</span>