Question

how to answer word problems based on time ,distance and speed in quadratic equation.

Answer 1

first read the question properly then write the important points required to solve it if u can't understand it You should make a diagram.
in time distance questions remember that
time = distance/speed
and convert values in time or speed to solve it.

Answer 2

For solving problems on time and distance, we use the following formulae:
Speed = Distance/Time, and
Time = Distance/speed.
Whenever speed is asked, take it as x km/hr or x m/sec

Always, form a correct equation using the variables.

For ex- question
1.A train travels a distance of 300 km/hr ay constant speed. If the speed of the train is increased by 5 km an hour, the journey would have taken 2 hrs less. Find the original speed of the train?

Sol: 
Let the constant speed of train be x km/hr.
Time taken to cover 300 km = 300/x hrs ............... ( time=distance/speed)
                                                               ....................1)
So time taken to cover 300 km when the speed is increased by 5km/hr = 300/x+5 hrs.........................2)

using 1) and 2) we get

300/x - 300/x+5 = 2 
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so, this is correct formulation.
now u can solve it easily for x

hope it helps u...........