If a certain wheel turns at a constant rate of...

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If a certain wheel turns at a constant rate of x revolutions per minute, how many revolutions will the wheel make in k seconds?

$$(A)60kx$$
$$(B)kx$$
$$(C)\ \frac{x}{k}$$
$$(D)\ \frac{x}{60k}$$
$$(E)\ \frac{kx}{60}$$

The OA is E.

Please, can any expert explain this PS question? I don't have it clear. Thanks.

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by [email protected] » Mon Oct 30, 2017 2:08 pm
Hi AAPL,

We're told that a wheel turns at a constant rate of X revolutions per MINUTE. We're asked for the number of revolutions that the wheel make in K SECONDS. This question can be solved in a couple of different ways; here's how you can get the answer by TESTing VALUES.

Let's TEST
X = 120 and K = 3
IF... the wheel makes 120 revolutions per MINUTE, then it makes 120/60 = 2 revolutions per second - so it makes 6 revolutions in 3 seconds. Thus, we're looking for an answer that equals 6 when X=120 and K=3. There's only one answer that matches...

Final Answer: E

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Rich
Contact Rich at [email protected]
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by Scott@TargetTestPrep » Sun Dec 03, 2017 5:46 pm
AAPL wrote:If a certain wheel turns at a constant rate of x revolutions per minute, how many revolutions will the wheel make in k seconds?

$$(A)60kx$$
$$(B)kx$$
$$(C)\ \frac{x}{k}$$
$$(D)\ \frac{x}{60k}$$
$$(E)\ \frac{kx}{60}$$
Since k seconds is k/60 minutes, the wheel will make x * k/60 = xk/60 revolutions in k seconds.

Answer: E

Scott Woodbury-Stewart
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