Linda needs to drive a total of 24 miles. So far, she has driven 5.6 miles. How many more miles must Linda drive?

To find out how many more miles Linda must drive, subtract the distance she has already driven from the total distance she needs to drive.

Total distance = 24 miles
Distance driven = 5.6 miles

Miles remaining = Total distance - Distance driven
Miles remaining = 24 miles - 5.6 miles = 18.4 miles

Therefore, Linda must drive 18.4 more miles.