Question

How many gallons of water in half acre pond 3 ft deep

Answer 1

let's firstly convert the acres to yd² and then to in³, since we know one in³ has about 0.004329 gallons(US).

So an acre is 4840 yd², so half that is just 2420 yd², now the pond is 3ft deep, namely 1 yard deep, so we're looking at 2420 yd² by 1 yd that's just 2420 yd³ in volume, now

`\begin{array}ll \cline{1-2} yd&36~in\\ \cline{1-2} (yd)^3&(36~in)^3\\ &36^3~in^3\\ &46656~in^3\\ \cline{1-2} \end{array}`

so since one yd³ has 46656 in³, how many in³ in 2420 yd³?

`\begin{array}{ccll} yd^3&in^3\\ \cline{1-2} 1 & 46656\\ 2420& x \end{array} \implies \cfrac{1}{2420}~~=~~\cfrac{46656}{x} \implies x=\cfrac{46656}{2420}\implies x=\cfrac{11664}{605}`

now, that's in³, how many gallons are in that?

`\cfrac{11664}{605}* 0.004329 ~~ \approx ~~ \text{\LARGE 977553.31}~gallons(US)`