2012 Excellence in Mathematics Contest Team Project Level I (Precalculus and above) School Name: Group Members: _________________________________________________________________________ _________________________________________________________________________ _________________________________________________________________________ _________________________________________________________________________ _________________________________________________________________________ _________________________________________________________________________ Reference Sheet Formulas and Facts You may need to use some of the following formulas and facts in working through this project. You may not need to use every formula or each fact. A bh Area of a rectangle C 2l 2w Perimeter of a rectangle A r2 Area of a circle y2 y1 x2 x1 Slope 1 A bh 2 Area of a triangle m a 2 b2 c 2 Pythagorean Theorem 5280 feet = 1 mile 3 feet = 1 yard 16 ounces = 1 pound 2.54 centimeters = 1 inch h 4.9t 2 v0t h0 C 2 r Circumference of a circle h 16t 2 v0t h0 1 kilogram = 2.2 pounds 1 meter = 39.3701 inches 1 gigabyte = 1000 megabytes 1 mile = 1609 meters 1 gallon = 3.8 liters 1 square mile = 640 acres 1 sq. yd. = 9 sq. ft 1 cu. ft. of water = 7.48 gallons 1 ml = 1 cu. cm. V r 2h V Area of Base height Volume of cylinder Lateral SA = 2 r h Lateral surface area of cylinder Volume b b 2 4ac 2a Quadratic Formula x 4 V r3 3 Volume of a sphere tan sin cos This team project is taken from The Mathematics Teacher, volume 105, Number 5, December 2011, National Council of Teachers of Mathematics (nctm.org) 2 TEAM PROJECT Level I 2012 Excellence in Mathematics Contest ____________________________________________________________________________________________ The Team Project is a group activity in which the students are presented an open ended, problem situation relating to a specific theme. The team members are to solve the problems and write a narrative about the theme which answers all the mathematical questions posed. Teams are graded on accuracy of mathematical content, clarity of explanations, and creativity in their narrative. We encourage the use of a graphing calculator. During a visit with his sister’s family, Ron Lancaster was shown an unusual bottle of Coca-Cola® that consisted of a sphere with a cap. Placing this bottle beside a can of Pepsi cola revealed the contrast (see photograph). Ron’s nephew Matt challenged Ron to pick the container that held the most liquid without touching either or making any measurements. Ron studied the bottle and can from a distance, picked the one he thought had the greater volume, and then found out he was wrong. Ron then mailed his colleague Doug Wilcock the spherical bottle with this challenge: Set it beside a Pepsi can and choose the container with the greater volume. Not only did Doug pick the right container, but he also devised the following set of questions related to the bottle and the can. Your task in this team project is to respond to these questions as clearly and accurately as possible. Have fun! Part 1 – Begin the Exploration If you were given the same challenge as Ron Lancaster, which container would you choose as having the greater volume? That is, without making any measurements or calculations, what does your gut instinct say? Explain. 3 Part 2 – With Measurements and Calculations 1. We can think of the Pepsi can as being a cylinder with a top in the shape of a frustum (A frustum is the portion of a cone or pyramid that remains after its upper part has been cut off by a plane parallel to its base. See the figure below). Use the measurements provided to determine the volume of the can. 4 Part 2 continued… 2. We now request that you use calculus to find the volume of the Coca-Cola bottle. If your team does not have a member with the necessary calculus background, then estimate the volume of the bottle by assuming it is a perfect sphere. a. A cross-section view of half the Coca-Cola bottle along with its measurements is shown in the figure. Use calculus to estimate the volume of a solid of revolution that models the spherical bottle. 5 Part 2 continued… b. The answer for part a. over-estimates the actual volume of the contents of the Coca-Cola bottle. The reason: The base is not flat but indented to provide more stability. A side view of the indentation is shown in the figure. Measuring indicates that AF 0.96 cm and AE 1.9 cm. What is the volume of the indented section? 6 Part 2 continued… c. If we take the calculated volume of the spherical bottle and subtract the volume of the indentation, we get the approximate net volume of the bottle. Doing so, can we reach a conclusion about the relative sizes of the spherical bottle and the cylindrical can? Explain. 7 Part 3 – Selling Soft Drinks Suppose that Coca-Cola were to sell these special bottles in packages of six arranged as shown in the photograph (two rows of three bottles). 1. If we define area efficiency as the ratio of the area of the bottles to the area of the container that will hold the bottles (see the figure below), how efficient is the rectangular six-pack? Express your answer as a simple ratio. 8 Part 3 – continued… 2. A second way to consider efficiency is to consider the ratio of the volume of the liquid in the containers to the volume of the packages (volumetric efficiency). The volume of soda in each bottle is 400 ml (400 cm3). The bottles are 11.4 cm high. What is the volumetric efficiency of the rectangular six-pack? 9 Part 3 – continued… 3. Another way of packaging the six bottles is to arrange them in the shape of a triangle (see photograph 3). (a) Determine the area efficiency of the triangular sixpack (see fig. 5). (b) Determine the volumetric efficiency of the triangular six-pack. 10 Part 3 – continued… 4. A creative idea for packaging the six bottles is to stack them in pairs to form barbells (see photograph 4). (a) What is the area efficiency of the barbell six-pack? In answering this question, remember that there are six bottles, not simply the three we see when we look at a plan of the package, as shown in figure 6. (b) What is the volumetric efficiency of the barbell six-pack? 11 Part 3 – continued… 5. Suppose that Coca-Cola decided to sell these unusual bottles in a highly original pack of seven, arranged as shown in photograph 5. (a) What is the area efficiency of the heptahex-pack (see fig. 7)? . (b) What is the volumetric efficiency of the heptahex-pack? 12 Part 3 – continued… 6. What type of package might you use for eight bottles? 13
© Copyright 2026 Paperzz