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A bus covers a certain distance everyday at a uniform speed . One day, after covering 30% of the distance , its speed decreased and the bus reached its destination 10 hours late. Had the decrease in speed occurred after the bus had covered 70 km more, it would have been late by only 9 hours. Find the total distance covered by the bus everyday.
There is a straightforward way... Please correct me if I'm wrong...
Let x be the distance traveled at the decreased speed. So the decreased speed can be equated as :
x/(10 hours) = (x-70)/(9 hours)
Solving,
9x = 10x - 700
i.e.,
x = 700, which is 70% of the total distance covered.
So, total distance : 1000km.
Download Time and Work shortcuts pdf for CAT, which covers concepts, formulas and tips on this topic.
The crux is to find the initial and the decreased speed. Let the initial speed be S1 and the decreased speed be S2
70/S2 - 70/S1 = 1 Once you find out S1 and S2, you can find the total distance.
