Word problem polynomial f(x) help

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Homework Help Overview

The problem involves a scenario where two individuals build a sandcastle with dimensions 36cm by 48cm by 60cm, but later discover that the box will be smaller due to a reduction in each dimension. The goal is to determine how much was taken off each dimension based on a specified volume reduction.

Discussion Character

  • Exploratory, Assumption checking, Problem interpretation

Approaches and Questions Raised

  • Participants discuss the formulation of a polynomial function p(x) representing the volume of the sandcastle after reducing each dimension by x. There are questions about the exact problem statement and the meaning of writing p(x). Some participants attempt to set the polynomial equal to a reduced volume of 62,208 and explore methods for solving it, including graphical and algebraic approaches.

Discussion Status

The discussion is ongoing, with participants exploring different methods to solve for the reduction in dimensions. Some suggest that a graphical approach may be necessary, while others express uncertainty about the correctness of their methods or the problem statement itself. There is no explicit consensus on the solution, but various interpretations and approaches are being considered.

Contextual Notes

Participants note discrepancies between their calculations and an answer booklet, raising questions about potential typos or misunderstandings in the problem statement. There is also mention of specific numerical values related to the volume reduction that are being debated.

Nelo
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Homework Statement




2 People build a sandcastle of 36cm by 48cm by 60cm. Later they learn that the box will be smaller; a certain amount will be taken off each of the length width and height


Homework Equations





The Attempt at a Solution



a) write a p(x)
> (36-x) (48-x) (60-x) , also x intercepts if (-x+36) = -(x-36) etc

b) graph (already did)
c) the amount of sand in the boc will be 3/5 of the amount in the design) , so i multiplied the l*w*h and then multiplied it by 3/5 and got the answer of 103,680 *3/5 = 62,208

d) How much was taken off each dimension? ( HOW DO I SOLVE THIS?) anyone? steps please
 
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any1?
 
Nelo said:
any1?

Before the answer we'd need a question.
 
Nelo said:

Homework Statement




2 People build a sandcastle of 36cm by 48cm by 60cm. Later they learn that the box will be smaller; a certain amount will be taken off each of the length width and height


Homework Equations





The Attempt at a Solution



a) write a p(x)
> (36-x) (48-x) (60-x) , also x intercepts if (-x+36) = -(x-36) etc
What do you mean, "write a p(x)" - A function that represents what?

Please give us the exact problem statement.
Nelo said:
b) graph (already did)
c) the amount of sand in the boc will be 3/5 of the amount in the design) , so i multiplied the l*w*h and then multiplied it by 3/5 and got the answer of 103,680 *3/5 = 62,208

d) How much was taken off each dimension? ( HOW DO I SOLVE THIS?) anyone? steps please
 
Nelo said:
c) the amount of sand in the boc will be 3/5 of the amount in the design) , so i multiplied the l*w*h and then multiplied it by 3/5 and got the answer of 103,680 *3/5 = 62,208

d) How much was taken off each dimension? ( HOW DO I SOLVE THIS?) anyone? steps please

Looks like you'll need to take p(x) and set it equal to 62,208:
(36 - x)(48 - x)(60 - x) = 62,208

However, unless you're allowed to solve it graphically using a graphing calculator, I'm not sure you can solve it algebraically (unless you know the cubic formula).
 
Um, Idk, the answer booklet says "approxmiately 9.28" , but yes I am on d) and that is the function...

your method did not work
 
If each dimension is reduced by 7.15 you get very close to the desired smaller volume.
 
Nelo said:
Um, Idk, the answer booklet says "approxmiately 9.28" , but yes I am on d) and that is the function...

your method did not work

Hmm, then either the answer booklet has a typo or you copied the problem wrong. I got the same answer that NascentOxygen got.
 

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