Question 344393
barbara rode her bike for 5 hours.
 her bike then developed flat tire so walked 3 hours to town.
 she covered 85 miles.
 if she rides 9 mph faster than she walks. how far did she walk.
:
Find the walking speed first
:
Let s = walking speed
then
(s+9) = biking speed
:
Write a distance equation; dist = speed * time
:
ride dist + walk dist = 85 mi
5(s+9) + 3s = 85
5s + 45 + 3s = 85
5s + 3s = 85 - 45
8s = 40
s = {{{40/8}}}
s = 5 mph is the walking speed
then
3(5) = 15 mi is B's walking distance
:
:
Check solution by finding the total dist
5(5+9) + 15 =
5(14) + 15 =
70 + 15 = 85 mi