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 

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Answer 1

$\blue{\bold{\underline{\underline{Answer:}}}}$

$\green{\tt{\therefore{(b)\:twice\:as\:much}}}$

$\pink{\bold{\underline{\underline{Step-by-step\:explanation:}}}}$

Let,

• Speed in the 1st trip be x miles/hour.
• So, speed in 2nd trip will be 3x miles/hour.

formula

Speed = $\frac{Distance}{Time}$

So, time taken to cover a distance of 50 miles on his first trip = $\frac{50}{x}$ hours.

and time taken to cover the distance of 300 miles on his 2nd trip = $\frac{300}{3x}$ hours = $\frac{100}{x}$ hours.

∴ His new time compared with the old time was $\bold\blue{(b)\:twice\:as\:much}$

Answer 2

Answer:

Step-by-step explanation:

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)