Question

A man travel at 30 km /h then the reaches his destination last by 10 minutes and if he travel at 42km/hr then the reaches 10 minutes earlier therfore the distance travelled by him is

Answer 1

let x be the distance and T be the time taken by it
so in case i
x/30=T-10....(1)
in case ii
x/42=T+10....(2)
now on adding these eqn we get x in term of T
then put the values in eqn i and ii u get your ans

Answer 2

Let the original time be x.
Time 1=(x+10)
Speed 1=30 km/h
Distance =speed ×time
=30×(x+10)
=30(x+10)

Time2=(x-10)
Speed 2 =42km/h
Distance=speed×time
=42(x-10)

According to the ques.
distance1=distance2
30(x+10)=42(x-10)
30x+300=42x-420
30x-42x=-420-300
-12x=-720
x=-720÷-12
x=60