Ram while driving to school has an average speed of 20 km/h. While returning from his school his average speed was 30 km/h. What is his average speed for the whole path or journey ?

Question

Answer

Calculating Average Speed

To calculate Ram's average speed for the whole journey, we need to use the formula:

Average speed = Total distance / Total time

Calculating Total Distance

We know that Ram travels to school and back, so the total distance covered is:

Total distance = Distance to school + Distance from school

We can assume that the distance to school and the distance from school are the same, so:

Total distance = 2 x Distance to school

Calculating Time

To calculate the time taken for the journey, we need to use the formula:

Time = Distance / Speed

For the journey to school, the time taken is:

Time to school = Distance to school / Speed to school

For the journey from school, the time taken is:

Time from school = Distance from school / Speed from school

The total time taken for the journey is:

Total time = Time to school + Time from school

Calculating Average Speed

Now that we have calculated the total distance and the total time taken, we can calculate the average speed for the whole journey using the formula:

Average speed = Total distance / Total time

Substituting the values we have calculated:

Average speed = 2 x Distance to school / (Distance to school / Speed to school + Distance to school / Speed from school)

Simplifying the equation:

Average speed = 2 x Speed to school x Speed from school / (Speed to school + Speed from school)

Therefore, Ram's average speed for the whole journey is:

Average speed = 2 x 20 x 30 / (20 + 30) = 24 km/h

Explanation

Ram's average speed for the whole journey is 24 km/h which is the harmonic mean of his speeds to school and from school. This is because the time taken to travel to school and from school is different due to the different speeds. Therefore, the harmonic mean is used to calculate the average speed.

Answer

Average speed = total distance / total time... suppose distance between home to scoohk is D..... ==> t1 = D / V1 & t2= D / V2 ===> Average speed = D + D / t1 + t2===> = 2 D / [ ( D / V1 ) + ( D / V2 ) ] = 2 / [ ( 1 / 20 ) + ( 1/ 30 ) ] = 2  *  600 / 50 = 1200 / 50 = 24 km / hr  IS THE YOUR ANSWERR... 💯💯💯

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