Watch Your Speed!
Two cars get closer by 9m every second while traveling in opposite directions (toward each other). They get closer by 1m every second while traveling in the same direction.
If the speeds of the cars are and , then find .
The answer is 20.
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Let X and Y be the velocities of the cars. Then, by the given problem,
X + Y = 9
X - Y = 1
Solving these equations, we get, X = 5 and Y = 4. Therefore X*Y = 20