Question

Jones covered a distance of 50 miles on his first trip. On a later trip he traveled 300 miles while going three times as fast. His new time compared with the old time was:

Answer 1

Let speed of the 1st trip x miles / hr. and speed of the 2nd trip 3x / hr.

We know that

Speed = Distance/Time.

Or, Time = Distance/Speed.

So, times taken to covered a distance of 50 miles on his first trip = 50/x hr.

And times taken to covered a distance of 300 miles on his later trip = 300/3x hr.

= 100/x hr.

Answer 2

Time = Distance/speed

Case 1
t1 = 50/v1

Case 2
t2 = 300/3v1 = 100/v1
t2/t1 = 2

So the new time is double of the initial time.