Answer:
30 miles
Explanation:
Let the number of days = d
in 1/3 of a day, or 1/3d, he drove 10 miles
The equation is:

To find out the number of miles driven in one whole day, we can multiply both sides by 3 or setting up a proportion
Method 1: Multiplying By 3
10 = 1/3d
10*3 = 1/3d * 3
30 = 1d
30 miles
Method 2: Proportions

10*3 = 1*1 Cross multiply
30 = 1
-Chetan K