Question 122320
Elliot began the journey at 8 am at 40 kilometers per hour. Benita began to chase him at 11 am at 50 kilometers per hour. What time was it when Bernita got within 60 kilometers of Elliot?
:
Let x = travel time of E, when he's 60 km ahead of B
Then
(x-3) = travel time of B, when he's with 60 km behind (started 3 hrs later)
:
Write a distance equation: Distance = speed * time
:
E's distance - B's distance = 60
40x - 50(x-3) = 60
40x - 50x + 150 = 60
-10x = 60 - 150
-10x = -90
x = {{{(-90)/(-10)}}}
x = + 9 hrs (after 8 AM)
:
AT 5 PM, B is within 60 km of E
:
Check solutions by finding the distance traveled by both 
40*9 = 360 km
50*6 = 300 km (started 3 hrs later)
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diff = 60 km