Question

$\mathfrak{\huge{\red{QUESTION}}}$

SOLVE THE FOLLOWING ​

Answer 1

■HEY DEAR

•°•suppose the school is at a distance of x km.

1》while driving to school , the average speed is 20 km h^-1. suppose the time while driving to school is t1.

NOW, Speed= d/ t

=》20= x/ t1

And , time taken , t1 = x/ 20h

2》on the return trip , the average speed is 30km h^-1. suppose the time taken for the return trip is t2.

NOW, Speed= d/time taken

=》30=x/t2

And time taken , t2= x/30 h

we will now consider the whole trip .

Total distance = x+x

(both ways) = 2x km

And, total time taken = x /20 + x / 30

=》 3x × 2x / 60

=》5x /60

=》x/12 h

NOW,

•°•Average speed = total distance covered / total time taken .

=》2x×12/x

=》24km h^-1

Thus, the average speed for abdul's trip is 24 kilometres per hour.

■HOPE ITS HELPFULL

◇◆◇BE BRAINLY◇◆◇

Answer 2

Case I:

While driving to school

Average speed of Abdul's trip = 20 km/h

Average Speed = Total distance/Total time taken

Total distance = Distance travelled to reach school = d

Let total time taken = t1

- (i)

Case II: While returning from school

Total distance = Distance travelled while returning from school = d

Now, total time taken = t2

Average speed for Abdul's Trip = Total distance covered in the trip/Total time taken

where,

Total distance covered in the trip = d + d = 2 d

Total time taken, t = Time taken to go to school + Time taken to return to school = t1 + t2

Concept Note - Consider the two cases individually to make the calculations clear and easy.

From equations (i) and (ii),

Hence, the average speed for Abdul's trip is 24 km/h.