Assertion (A): If an inlet takes longer to fill a tank than an outlet takes to empty it, opening both empties a full tank.
Reason (R): The outlet's rate is then greater than the inlet's, so the net rate is negative.

Both A and R are true, and R is the correct explanation of A.Correct answerYour answerBoth A and R are true, but R is not the correct explanation of A.Correct answerYour answerA is true, but R is false.Correct answerYour answerA is false, but R is true.Correct answerYour answer

Show the answer and explanation

CorrectNot quiteAnswer A

Correct answer: A

R: a longer time means a smaller rate, so $\frac{1}{a} - \frac{1}{b} < 0$ when $a > b$ . True.
A negative net rate means the water level falls, so A is true because of R.

Concept: The net rate of an inlet and an outlet
Typical timeTypical: 60 s
Your timeYours: —

The rule this testsOutlets and leaks

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Ten questions from Boats & Streams, Pipes & Cisterns, at your own pace.

Assertion (A): If an inlet takes longer to fill a tank than an outlet takes to empty it, opening both empties a full tank.Reason (R): The outlet's rate is then greater than the inlet's, so the net rate is negative.

Explanation

Assertion (A): If an inlet takes longer to fill a tank than an outlet takes to empty it, opening both empties a full tank.
Reason (R): The outlet's rate is then greater than the inlet's, so the net rate is negative.