Question

Anis completed a journey of 4.5 km by walking for 30 minutes at

a certain speed, and then by running another 25 minutes at a speed
which is 2km/h more than the walking speed. Find her walking
speed in km/h.​

Answer 1

speed=d/t

let him cover x distance while walking

running d=4.5-x

s1=x/0.5 km/hr....(1)

s2=4.5-x//5/12.....(2)

atq.....s2=2+s1

s1=2x

s2=54-12x/5

by eqn 1 and 2

s1+s2=2x+54-12x/5

putting value of s2

s1+2+s1=2x+54-12x/5....taking LCM =5

10s1+10= 10x+54-12x

as s1=2x

10s1+10= -2x+54

10s1+10=-s1+54

11s1=44

speed when walking=4km/hr