Question

a boy travels A to B with a constant speed 10 km\h and then from B to A with a speed of 20 km\h.Find the average seed of the body for the trip ​

Answer 1

Answer:

10km/h is the answer

Explanation:

Answer 2

Explanation:

Given :-

A boy travels A to B with a constant speed 10 km\h and then from B to A with a speed of 20 km\h.

To find :-

Find the average seed of the boy for the trip ?

Solution :-

10 km/hr ----->

A__________________B

<------ 20 km/hr

Let the distance from A to B be X km

The speed of the boy travels A to B = 10 km/hr

We know that

Distance = Speed × Time

=> Time = Distance / Speed

=> Time taken for traveling from A to B

=> X/10 hr.

And

The speed of the boy travels B to A = 20 km/hr

Time taken for traveling from B to A

=> X/20 hr

Total distance travelled by the boy =

Distance from A to B + Distance from B to A

=> X+X = 2X km

Total time taken for travelling = (X/10)+(X/20)

LCM of 10 and 20 = 20

=> (2X+X)/20

=> 3X/20 hr

Now , The average speed of the boy

=> Total distance / Total time

=> 2X/(3X/20)

=> 2X×(20/3X)

=> (2X×20)/(3X)

=> 40X/3X

=> 40/3 km /hr

=> 13 1/3 km/hr

Answer:-

The average speed of the boy in the trip is 40/3 km/hr or 13 1/3 km/hr

Used formulae:-

• Distance = Speed × Time