Question 1162830
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Let *[tex \Large x] represent the number of cars and *[tex \Large y] represent the number of trains at the beginning.


Then we know that *[tex \Large \frac{x}{y}\ =\ \frac{2}{3}] which is the same as:


*[tex \LARGE \ \ \ \ \ \ \ \ \ \ 3x\ =\ 2y]


After the purchase of the 30 cars, the situation changed to:


*[tex \LARGE \ \ \ \ \ \ \ \ \ \ \frac{x\,+\,30}{y}\ =\ \frac{3}{4}]


Which is to say:


*[tex \LARGE \ \ \ \ \ \ \ \ \ \ 4(x\,+\,30)\ =\ 3y]


Solve the 2X2 system for *[tex \Large y]
								
								
John
*[tex \LARGE e^{i\pi}\ +\ 1\ =\ 0]
My calculator said it, I believe it, that settles it
<img src="http://c0rk.blogs.com/gr0undzer0/darwin-fish.jpg">
*[tex \Large \ \
*[tex \LARGE \ \ \ \ \ \ \ \ \ \  
								
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