Kara walks A. 3 2/5 miles
Explanation:
Step 1; We must calculate how much 2/5 miles is. 2/5 miles equals 0.40 miles. Kara walks this distance times 8 1/2. 8 1/2 times equals 8.5 times. So the distance she walked is the number of loops walked × distance of each loop.
Total distance walked = Number of loops walked × distance of each loop
= 8.5 loops × 0.20 miles = 3.4 miles
Step 2; In order to check which option this is, we must know what values all the given options are equal to
A. 3 2/5 miles equals 3 miles + 2/5 miles = 3 + 0.20 = 3.20 miles.
B 4/85 miles equals 0.047 miles which is lesser than one loops distance.
C. 8 9/10 miles equals 8 miles + 9/10 miles = 8 + 0.90 = 8.90 miles
D. 21 1/4 miles equals 21 miles + 1/4 miles = 21 + 0.25 = 21.25 miles.
So the answer is option A.