Answer:

your answer is 3 hours

5 into 15 = 3

Verified answer

Step-by-step explanation:

filed cistern = 5/15

rest cisten= 1- 5/15

rest cistern= 10/15

rest cistern= 2/3

time taken to fill 5/15 cistern= 1hr

time taken to fill 1 cristern= 1×15/5

time taken to fill 1 cristern= 3hr

time taken to fill 2/3 cistern= 3× 2/3

time taken to fill 2/3 cistern= 2hr.

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