Question 943982: car a and car b are 100 kms apart from each other travelling at different speeds. if they travel in same direction they meet after 5 hrs and if they tavel towards each other they meet in 1 hour.. find the speed of both cars
Answer by ankor@dixie-net.com(22740)   (Show Source):
You can put this solution on YOUR website! car a and car b are 100 kms apart from each other travelling at different speeds.
if they travel in same direction, they meet after 5 hrs and
if they travel towards each other they meet in 1 hour..
find the speed of both cars
:
let a = car A's speed
let b = car B's speed
Then
(a + b) = their relative speed going towards each other
and
(a-b) = their relative speed going the same direction
:
Write distance equation for each scenario; dist = time * speed
5(a - b) = 100; going the same direction
1(a + b) = 100; going towards each other
We can simplify the 1st equation, divide both sides by 5, the 2nd equation can be left alone, we have then:
a - b = 20
a + b = 100
-------------Adding eliminates b, find a
2a = 120
a = 120/2
a = 60 mph the speed of A
Use the 2nd equation to find b, replace a with 60;
60 + b = 100
b = 100 - 60
b = 40 mph is the speed of B
:
:
Check this in the 2nd equation, replacing a and b
5(60 - 40) = 100
5(20) = 100
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