Question

Stardust the unicorn, covered a distance of 50 miles on his first trip to the forest. On a later trip he travelled 300 miles while going three times as fast. His new time compared with the old time was:

A.The same
B.Twice as much
C.a third as much
D.three times as much

Answer 1

Hey


It must be B but i am not do sure about it.

Answer 2

His new time compared with the old time was b. Twice as much.

Given:

Distance covered in first trip: 50 miles

Distance covered in later trip: 300 miles

Solution:

Let the speed in the first trip be x.

Thus, the speed of the later trip will be 3x.

We know that,

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

Therefore, time taken on the first trip $= \frac{50}{x}$

Time taken on the later trip $= \frac{300}{3x}$

Thus, on comparing new time with the old time, we get,

$\frac{50}{x}=\frac{300}{3 x}$

$\Rightarrow \frac{50}{x}=\frac{6[50]}{3 x}$

$\Rightarrow \frac{50}{x}=\left(\frac{6}{3} \times \frac{50}{x}\right)$

$\Rightarrow \frac{50}{x}=2 \times \frac{50}{x}$

Thus, on comparing, new time is twice as much old time.