what kind of grade would you give this???

Question

(i'm in 9th grade)



BY ******* ******
March 25, 2007


The freshman class is desperate for funds, so they decided to have a fundraiser. They decided to make containers out of poster board and masking tape, and they will sell popcorn and their containers. I need to find the largest volume to make the container. Each container is made out of 91x61cm of poster board. And I need to calculate the cost for each container of popcorn if the cost of the popcorn is $0.000006/cm.
The way I am going to solve this problem is multiplying 91 and 61 that will give the area of the poster board. Then I will take that number and divide it by 5 because there are 5 sides. And find the square root of that number and then I got my dimensions for each side. That was my successful method. (My only method)
I am confident that my answer is correct because I used the formula to find volume. And I know that this answer is correct because I checked it.
My solution is 33...continued...

My solution is 33.3cm x 33.3cm per side. This is the biggest dimension from one 61x91cm-poster board. The volume of this popcorn container is 36959.31369cm3. So if each cubic centimeter cost $0.00006/cm3 one container of popcorn would cost $2.21.

Answer 1

??? C
First problem, there is not a way to make 33x33 sudes with the original dimensions on the piece of cardboard. The only way to do this is to cut it many many times and tape or glue it back together.

by making a cube you get close to the shape with the smallest surface area (amount of cardboard needed) and largest volume. A sphere! I highly doubt your teacher is expecting you to come up with some part of a sphere to answer this question.

What I am thinking of is take the original rectangle and cut squares out of the corners fold up the sides and tape the edge.
Easiest if you draw a picture! 61 x 91
Draw small squares in eacher corner diminsion X
If you were to fold up the side your box would end up X deep by 61- 2x wide by 91 - 2x long
X * (61 -2x) (91- 2x) = x (5551 + 304x + 4x^2)
=5551x -304x^2 + 4x^3
now find the maximum of the function (derivative calculus)
or make an input out put table
try values of x until you find the highest answer

Answer 2

Well, the English could use a little tweaking, but I'm assuming that this is for a math class, so that shouldn't matter that much. And why is the popcorn so cheap/such an infinitesimally small number being used? That's like... 6 thousandths of a cent...

But yeah, I suck at math, so I can't help you there.

Answer 3

If you are just being graded on the math: A+
If you are being graded on the math and grammar: C

I can edit your grammar if you'd like me to. Just email me at [e-mail] or message me to let me know! =)

Answer 4

Sounds good to me, your basic idea is fairly sound, i'd give you a B+ or above

Answer 5

you shouldn't use I and they so much in a story problem...there is supposed to be a scenario in a story problem