kiran120680 wrote:
A man needs to travel a certain distance. He travels a certain distance by car and the rest by train. Car travel costs him $12 per km and traveling by train cost him $8 per km. If the total amount spent on car travel was x% of the total amount spent on whole journey and the total distance travelled by car was y% of the total distance covered, what is the value of y in terms of x?
A. x/(100-x)
B. 200x/(300-x)
C. 300x/(200-x)
D. 200x/(x-300)
E. None of these
The question has already been discussed. Please check before posting..
As for the solution..
Best way would be to take value of x and yLet the total distance be 100, in which 50% is traveled by each mode, so y=50%.
Total amount spent = 12*50+8*50=1000.
so x = \(\frac{12*50}{1000}\)=60%
Let us check the value that gives us an answer 50%.
A. \(\frac{x}{100-x}=\frac{60}{100-60}=\frac{60}{40}\)...NO
B. \(\frac{200x}{300-x}=\frac{200*60}{300-60}=\frac{12000}{240}=50\)...YES
C. \(\frac{300x}{200-x}=\frac{300*60}{200-60}=\frac{18000}{140}\)...NO
D. \(\frac{200x}{x-300}=\frac{200*60}{60-300}=\frac{12000}{-240}=-50\)... Cannot be negative... NO
E. \(\frac{300x}{100-x}=\frac{300*60}{100-60}=\frac{18000}{40}\) or None of these... NO
Thus B
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