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2 years ago

12

A tank can be filled by one pump in 50 minutes and by another pump in 60 minutes. A third pump can drain the tank in 75 minutes.

If all 3 pumps go into operation, how long will it take to fill the tank? help pls

1 answer:

Lubov Fominskaja [6]2 years ago

3 0

It sure take a hours to pump in the tank

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Hello!

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[(82.3-81.2) ± 1.708* (6.11* $\sqrt{\frac{1}{15}+\frac{1}{12} }$ ]

[-2.94; 5.14]

Using a 90% confidence level you'd expect the interval [-2.94; 5.14] to contain the true value of the difference between the average percentage obtained in calculus by boys and the average percentage obtained in calculus by girls.

I hope this helps!

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