X takes 3 hrs more than Y to walk 30 km. But, if X doubles his pace, he is ahead of Y by 1.5 hrs. What is their speed of walking?
2 Answers
Explanation:
Assuming that both
In fact, the time it takes to
As for the second sentence, if
We can solve the system by subtracting
which can be written as
solving for
Substitute this value for
which leads to
Explanation:
Speed (
#"v" = "d"/"t"#
For first case
It’s given that
So,
For second case
“X doubles his pace” means X doubles his speed. So speed of X now is
“X is ahead of Y by 1.5 hrs” means now X takes 1.5 hrs less than Y to travel same distance.
So, time tiken by X to travel 30 km is now
Substitute

#"v"_"X" = 30/"t"_"X" = 30/("t"_"Y" + 3) = 30/(6 + 3) = 30/9 = 10/3# 
#"v"_"Y" = 30/"t"_"Y" = 30/6 = 5#