Investigation: The open box problem.
Investigation: The open box problem Problem: An open box is to be made from a piece of card. Identical squares are to be cut off the four corners of the card to make the box. (As shown below) Cut off Fold lines Aim: Determine the size or the square cut which makes the volume of the box as large as possible for any given rectangular sheet of card. Plan: To start of with I will be using the trial and improvement method to experiment with different sizes of a square boxes. By doing this I will find out the size of cut off that will leave me with the largest volume inside the box. To find out the volume I will need to know the size of the cut off side and the base length. x = length off the square cut off L = original length off the square card The formula that I will use to work out the volume is: Volume = (L-2X) ²X. The different sizes of cards that I will be using are 10cm, 11cm, 12cm, 13cm and 14cm. I will determine the size of x that will give the highest volume to 2d.p. After finding the highest value of X I will prove that my answer if right by using differentiation. Finally I will try and find a rule that allows me to find the highest value of X for a piece of square card and check that it works with any size of square card. Trail and improvement Size of card - 10cm by 10cm X must be 0<X<5: This is because if X is 0 there would not be a side to fold and if