Answer: 320 miles
Step-by-step explanation:
Let the miles that they drove be represented by x.
Since Sarah drove two-fifths of the miles which is 128 miles, then the total miles would be:
= 2/5 × x = 128
0.4 × x = 128
0.4x = 128
x = 128/0.4
x = 320
The total miles is 320 miles.