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One pump can fill a tank with oil in 10 hours. Together with a second pump, it can fill the tank in 6 hours. How long will it take the second pump to fill the tank if it is used alone?

User Rmhrisk
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2 Answers

4 votes

Answer:

The first pump can do 1/0 of the work per hour

Together they do 1/6 of the work per hour

The second alone would do (1/6 - 1/10) of the work per hour.

1/6 - 1/10 = 1/15

The second pump would take 15 hours to do the work.

C) 15

Hope this helps. :)

User Perymerdeka
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7.9k points
0 votes

Answer:

The second pump can fill a tank with oil in 15 hours.

Explanation:

It is given that one pump can fill a tank with oil in 10 hours. Together with a second pump, it can fill the tank in 6 hours.

Let the second pump can fill a tank with oil in t hours.

One hour work of first pump is
(1)/(10).

One hour work of second pump is
(1)/(t).

One hour work of both pump together is
(1)/(6).

1 hour work of both = 1 hour work of 1st pump + 1 hour work of 2nd pump


(1)/(6)=(1)/(10)+(1)/(t)


(1)/(6)=(t+10)/(10t)

Cross multiply.


10t=6(t+10)


10t=6t+60

Subtract 6t from both the sides.


10t-6t=60


4t=60

Divide both the sides by 4.


t=15

Therefore the second pump can fill a tank with oil in 15 hours.

User Reflic
by
8.6k points

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