Atank 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? pls

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  42 6/7 minutes

Step-by-step explanation:

In each minute, the first pump adds 1/50 of a tankful, the second adds 1/60, and the third subtracts 1/75. Then at the end of each minute, the amount added to the tank is ...

  1/50 +1/60 -1/75 = (6 +5 -4)/300 = 7/300 . . . tankful

The time required to fill the tank is the reciprocal of this rate:

  1/(7/300 tankful/minute) = 300/7 minutes/tankful

  300/7 minutes = 42 6/7 minutes

hope this !

step-by-step explanation:

d = distance between moon and sun, which in this problem is the hypotenuse of a right triangle.  

the distance y is the side opposite to angle x in the right triangle.   use the definition of the sine function from basic trigonometry.

sin(x) = y/d ⇒

d = y/sin(x)