# Trick for solving Time and Distance Questions Shortcut #1

Time and Distance problems are asked in most of the competitive and other exams. Usually this type of questions takes time in solving them through normal way. Time is a crucial term in competitive examinations as you have a very limited time for solving questions in competitive examination. You have to save time by solving questions quickly which is very hard to implement. But if you learn few shortcut methods of solving these question, you can save a quite appreciable time. You might also know some of the tricks already but here on this site are very short tricks which will let you solve question on your fingertips. Here is a shortcut trick #1 for solving distance problems.
First let us learn conversion
For converting m/s into km/h, multiply by 18/5.

For converting km/h into m/s, multiply by 5/18.

Speed=distance/time
Time=distance/speed
Distance=speed*time

We will understand this trick with an example.

Q:- A train covers a distance of 50 km  with a speed of 40km/hr and next 60 km with a speed of 30 km/hr  in travelling from A to B . What will be the train’s average speed during the whole journey?
Now here is a shortcut trick rule for this question.
If d1=first distance=50 km (given in above example)
And d2=second distance=60 km (given in above example)
And X=first speed=40 km/hr (       “           )
And Y=second speed=30 km/hr
Then average speed={(d1+d2)XY}  /{(d1Y+d2X)}

Putting the value of d1, d2,X and Y from the given example in the above formula
We get

Average speed= {(50+60)40x30}/{(50x30)+(60x40)}
Average speed=(110x40x30)/(1500+2400)
=(110x40x30)/3900
=(110x12)/39