Question

$\mathcal\red{Question}$
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:

(a) three times as much
(b) twice as much
(c) the same
(d) half as much
(e) a third as much​

Answer 1

━━━━━━━━━━━━━━━━━━━━━━━━━

$\text{\large\underline{\orange{Solution:-}}}$

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

$\text{\large\underline{\pink{We\: know\:that:-}}}$

$\bold{Speed \:=\: Distance/Time.}$

Or, Time = Distance/Speed.

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

And times taken to covered a distance of 300 miles on his later trip

$\text{\large\underline{\orange{=300/3xHr.}}}$

$\text{\large\underline{\orange{= 100/xHr.}}}$

So we can clearly see that his new time compared with the old time was: twice as much.

━━━━━━━━━━━━━━━━━━━━━━

Answer 2

→  Solution:

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.

So we can clearly see that his new time compared with the old time was: twice as much.

Answer: (b)