Catch the Thief!

Classical Mechanics Level 1

A Policeman saw a Thief at a distance of $200$ metres. The Policeman and the Thief started running at the same time. If the Policeman runs at a speed of $4\frac{1}{6}$ metres per second and the Thief at a speed of $3 \frac{1}{3}$ metres per second, after what time (in seconds) will the Policeman catch the Thief ?

The answer is 240.

1 solution

Dhananjay Dhiman
Feb 22, 2015

Suppose the Policeman will catch the Thief after 't' seconds.

Then,

( $\dfrac {25}{6} - \dfrac {10}{3}) t$ = 200

$\Rightarrow$ $\dfrac {5}{6}$ t = 200

$\Rightarrow$ t = $\dfrac {200 \times 6}{5}$ = 240 seconds = 4 minutes.

And, 4 minutes = $60 \times 4$ = $\boxed {240 Seconds}$ .

Sum of the digits of Seconds = 2+4+0 = $\boxed {6}$ .

Hence, the answer is $\boxed {6}$ .

Dhananjay, thanks for posting a problem. In future, please use the relevant level for a problem. This is clearly not a level 4-5 problem, as it is more of a level 1-2 problem. I have adjusted the level accordingly.

Also, I would appreciate it if you used the correct topic. This is not a number theory problem, but an algebra or mechanics problem.

I look forward to seeing you post better problems over time :)

Calvin Lin Staff - 6 years, 3 months ago

OK Thanks for rectifying my errors. I look forward for not committing such mistakes again.

Dhananjay Dhiman - 6 years, 3 months ago

Catch the Thief!

The answer is 240.

1 solution

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