Answer:
It would take 8 days 18 hours for 4 pipes to empty the tank.
Step-by-step explanation:
To solve this, first, we need to check if this is a direct or indirect proportion
As the number of pipes increases, the number of days to empty a water tank decreases, as the number of pipes decreases, the number of days it takes to empty a water tank increases. This is an indirect proportion.
Solving using proportion;
since it is an indirect proportion, the arrangement differs from that of the direct proportion, it will be arrange inversely to each other
Let x be the number of days it will take to empty 4 pipes
7 pipes = 4 pipes
x = 5 days
cross-multiply
4×x = 7×5
4x = 35
Divide both-side of the equation by 4
4x/4 = 35/4
x = 8.75 days
But we are asked to leave our answer in days and hour
8.75 days = 8 days + 0.75 days
0.75 day is not up to a day, so we will change it to hour
0.75 day = 0.75 × 24 hours = 18 hours
8.75 days = 8 days 18 hours.
Therefore, it would take 8 days 18 hours for 4 pipes to empty the tank.
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