D= distance
t= time
s= speed
FORMULA
Distance= speed * time
STEP 1:
Find total distance
Jim's D + John's D= 3 miles
STEP 2:
Distance= (Jim's speed * time) + (John's speed * time)
D= 4t + 5t
3 miles= 9t
divide both sides by 9
3/9= t
reduce by 3
1/3 hour= t
STEP 3:
1 hour= 60 minutes
=1/3 * 60
=(60/3)
= 20 minutes
ANSWER: They will travel 20 minutes before they meet.
Hope this helps! If it does, please mark me brainliest! :)