Aptitude - Time and Distance - Discussion

0.9 km per minute, what it implies about? lost distance or no.of stoppages?

As speed of bus without stoppage is 54 kms per hour (i.e) in 1 hr bus travels 54 kms.(as Distance = speed *time).

Similarly as speed of bus with stoppage is 45 kms per hour (i.e)in 1 hr bus travels 45 kms(as Distance = speed *time).

Comparing the cases we can see that bus with stoppage covers 9 km less than the bus without stoppages.

Now we know that bus covers,

54 kms in 60 mins (1 hr)
1km in 60/54 mins
9 kms ---------------------- 60/54*9 = 10mins.

So with original speed of 54 km/h, bus stops for 10 mins.

Can it be solved using x and y?

I tried by this method:

- - - Speed Time Distance.
Stop : 54 1h D.
Non-S: 45 1-X h D.

D is common for both, so,

54 * 1h = 45*(1-x)h.

X = 1/5 hr ==> 12 mins.

What went wrong in this method.

Why we get 54 as denominator?

As we have subtracted the two speeds, then it would result as 9 kmph!

If 54 kmph means for 1hr------> 54km.

So now 9 kmph means 1hr------> 9km right so the answer is 60min.

Answer is coming 12 min,
s = d/t.

54 = d because t = 1hr given -------- 1,
s = d/t.

45 = 54/(t+1) ------- 2.
By solving we get 12.

A car starts running with the initial speed of 40 km/h with its speed increasing every hour by 5 km/h. How many hours will it take to cover a distance of 385 km?

@Brijesh Kesharia,

40 + 45 + 50 + 55 + 60 + 65 + 70 = 385.

So, it takes 7 hrs.

@Dushanthi,

Is there any shortcut method for solving the same problem (Brijesh Kesharia's que. ) for more complex data?