Answer :
The water cooler tank has to be filled 18 times to quench the thirst of 1200 students.
We have
Number of students= 1200
Water consumption per student= 750 ml
So, Total water consumption
= Number of students × Water consumption per student
= 1200 × 750 ml
= 900000 ml
= 900 Liter
Now, the time cooler tank has to be filled to quench the thirst
= 900 / 50
= 18 times
Thus, the water cooler tank has to be filled 18 times to quench the thirst of 1200 students.
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