Question

a man cover a distance of 21 km in 4.5 hrs partly by running and partly by walking . if he walks at 5 km / hrs and run at 11 km/ hrs find the distance he cover by walking solved with ans​

Answer 1

Answer:

total distance = 21 km

total time  = 4.5 hrs

velocity by walking = 5 km / h

velocity by running = 11 km/h

distance travelled by walking be x

and distance travelled by running be  21-x

and time taken in walking be  y

time taken in running be   4.5-y

v=d/t    

d =vt

x=5y ---------(1)

21-x = 11 ( 4.5-y )

21-x = 49.5-11y

11y-x= 28.5 -------------(2)

we know that  x = 5y

11y-5y=28.5

6y = 28.5

y = 28.5/6

y = 4.75 hrs

so distance travelled by walking is

x = 5y

 = 5( 4.75 )

 =   23.75 km

there fore  distance travelled by walking is 23.75 km