Question

it takes a hose 4 minutes to fill a rectangular aquarium 9 inches long, 13 inces wide, and 14 inces tall. how long will it take the same hose to fill an aquarium measuring 21 inces by 25 inces by 34 inces?

Answer 1

Answer: 43.58 min

Explanation:

Knowing the volume of a rectangular object is length x width x height, we have two volumes:

$V_{1}=(9 in)(13 in)(14 in)=1638 in^{3}$

$V_{2}=(21 in)(25 in)(34 in)=17850 in^{3}$

And we know it takes a time of 4 minutes to fill $V_{1}$.

If we want to know how long will it take the same hose to fill another tank with volume $V_{2}$, we can use the Rule of three, which is a mathematical rule to find out an amount that is with another quantity given in the same relation as other two also known:

$1638in^{3}$ ---- $4min$

$17850in^{3}$ ---- $?$

$?=\frac{(17850 in^{3})(4min)}{1638 in^{3}}$

Finally:

$?=43.58 min$