Question

If a body moves from home to school with 30km/h and return to back with 40 km/h.find average speed.

Answer 1

Answer:

Explanation:

we know that

average speed = total distance travelled divided by total time taken

let distance from home to school be x

then

time = distance / speed

therfore time needed to home to school is

time = x/ 30 (1)

again,

time taken for to reach from school to home is,

time = x/ 40 (2)

From average speed formula

average speed= (x+x)/ ( x/30 +x/40)

=2x / ( 70x /1200)

= 2400x / 70x

= 342.8 km/ hr