Question

Plzz help me guys....

Answer 1

let the workdone by all the three pipes be x
work done by 1st pipe in 12 min=x
work done by 1st pipe in 1 min=x÷12
work done by 2nd pipe in 1 min=x÷15 word done by waste pipe in 1 min =x÷10

1÷12+1÷15-1÷10. = x
take LCM

Answer 2

12.

  The inlets pipes filled the part of this bath in a min. = 1/12 + 1/15

                                                                                              = 9/60 = 3/20 th part.

The waste pipe can empty the part of bath in a min . = 1/10 th part.    

            If the two inlets pipes are opened along with waste pipe      (accidentally).

Now ,

Part of this bath filled in a min. = 3/20 - 1/10 = 1/20 th part.

So

Now the time taken to fill this bath = 20 min

Thank u.

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