a rectangular storage container with an open top is to have a volume of 10m^3. the length of this base is twice the width. material for the base costs $5 per square meter. material for the sides costs $3 per square meter. find the cost of materials for the cheapest such container. round to the nearest cent.

Question

anonymous · Answer

i put in $129.8 but it was marked as wrong. can anyone explain to me why? and what the real answer is?

anonymous · Answer

do you have your solution?

anonymous · Answer

Do you know the correct answer? i got $100. Not sure though

anonymous · Answer

no i don't have the solution

anonymous · Answer

can you show me how you got $100?

anonymous · Answer

i wrote it in a paper and its a little messy, is it ok?

anonymous · Answer

yeah, sure

anonymous · Answer

w8, ill write it down for ya

anonymous · Answer

thanks

anonymous · Answer

alright, now i got a different answer. don't know whats wrong with me today! i got $81.77. ill post the solution anyway.

anonymous · Answer

it's ok, i was having the same problem before

anonymous · Answer

anonymous · Answer

that's weird, i also got the cube root of 9/2 in that last part, but plugging it back in i got an answer of 129.80

anonymous · Answer

lemme recheck then

anonymous · Answer

Nope. still the same answer

anonymous · Answer

did you have the same cost equation?

anonymous · Answer

omg i just reviewed my answer and realized i had a minor calculation error in the beginning which lead me to the same equation as you. you must be right

anonymous · Answer

it's a shame i didn't notice this before...

anonymous · Answer

the correct equation is 10w^2+90/w, the same as yours, so the answer should be 81. 78