Task of the Week – Page 10

As a task creator for MathCityMap, it is important to look at the environment through “mathematical glasses”. Thus, buildings become cuboids, lawns become polygons or – as in the current task of the week – greenhouses become half cylinders.

Task: Arched greenhouse (task number: 1950)

Calculate the material requirement for plastic for the greenhouse. Give the result in m².

When solving the task, students’ mathematical view is also taught. This involves the recognition of the object as a lying half cylinder. Once this has been achieved, radius, the circumference of the semicircle and height must be measured, so that the material consumption can be calculated. This corresponds to the surface of the half cylinder, which can be determined by means of formulas for the area of a circle and the surface of a cylinder.

Through cooperation with the MOOC Working Group of the University of Turin, we are looking forward to the first MCM tasks in Italy, which is part of today’s Task of the Week.

Task: Height of the Building (task number: 2045)

Determine the height of the building. Give the result in meters.

The height can be approximated in various ways, e.g. by estimation or the intercept theorems. The task can be solved elegantly by looking for structures and patterns in the building facade. In this building, the horizontal strips, which can be found up to the roof, are noticed directly. For the total height, it is therefore only necessary to determine the height of a horizontal strip, as well as to count the number of strips. Minor deviations from the pattern can be approximated using estimates.

With this method, the task can already be solved by class 6 students. In the case of older pupils, the different solutions can be discussed and assessed with regard to simplicity and accuracy.

In this year’s autumn, numerous tasks were created in Wilhelmsburg, district of Hamburg. The tasks are very convincing – especially in the context of the MCM concept – through their interdisciplinary and thematic diversity, which we would like to illustrate exemplary in our current Task of the Week.

Task: Red area (task number: 1964)

Determine the red area on which the ping-pong table stands. Give the result in m².

It quickly becomes clear that the entire area can not be approximated by a single geometrical object, or that this is only possible with significant losses in accuracy. It is therefore appropriate to divide the area searched into disjoint subspaces, which can be calculated using formulas. This is best done using a drawing. A particular challenge are the curved edges, where estimations and approximations are necessary. According to measurements and calculations, the total area is obtained by adding the area contents of all partial surfaces.

The area can be described using rectangles and triangles. In addition, the principle of the decomposition and additivity of surface content is necessary for solving the problem. The task can be used from class 7 onwards.

As a few weeks ago, the Task of the Week leads us to the African continent, more precisely to the approximately 1000-meter-high Tafelberg in Cape Town. There you can find a monument of stone, which is also an ideal object for a MCM task.

Task: Tafelberg’s Monument (task number: 1791)

Calculate the mass of the stone monument. Give the result in kg. 1 cm³ of granite weighs 2,6 g.

First, the shape of the stone has to be considered more closely. When choosing a suitable model, a prism with a trapezoidal base can be used. For this, it is necessary to ignore minor deviations from the ideal body as well as to operate with the stone mentally. The required data are then determined and the required weight of the stone is obtained by means of the area content formula of a trapezoid, the volume formula of a prism and the given density.

The task shows that over the last few years, MCM has developed into an international platform for authentic “outdoor” mathematic tasks and has already been set up in many prominent places. We are looking forward to further tasks and are looking forward to the countries and regions in which new MCM tasks will emerge.

As a part of a teacher training at the Johanneum Gymnasium Herborn, a modeling task was created, which we would like to present to you today as the “Task of the Week”.

Task: Brick in the Wall (task number: 2040)

The wall in the schoolyard should be sprayed. It is planned to save color for the hole in the wall. Calculate the area to be sprayed in m². Enter the result with two digits.

The challenge in this task is to approach the existing hole in the rectangular wall as precisely as possible. Different models can be chosen for this purpose. On the one hand, one could assume the hole as a circle and determine an average diameter. More precisely, however, the result is obtained by approaching the hole as an ellipse and measuring the axes.

The task requires a certain amount of creativity and shows that the clear mathematics in the environment outside the classroom reaches its limits. The pupils acquire modeling competences, especially in the skillful choice of a mathematical model. The various solutions and results of the pupils thus form an ideal basis for discussing appropriate models. The problem can be applied with the treatment of circle and ellipse from class 9 onwards.

Today, we would like to introduce you a task from Speyer, which was created there by Katalin Retterath. It is about the famous Way of St. James, which leads through the city to Santiago de Compostela.

Task: Jacobean Pilgrim (task number: 1614)

Measure/estimate the step of the Jacobean Pilgrim. How many steps would he have to take if he were to travel the 2,500 kilometers to Santiago de Compostela?

How did you get the idea to create MathCityMap?

I am a consultant for teaching development in mathematics at the Pedagogical State Institute in Rhineland-Palatinate. For a number of years, we have been developing mathematical rallies, which are well received by both our pupils and the training events. First we experimented with LearningApps, then with Actionbound – both were OK, but not really satisfactory. We have become acquainted with MathCityMap and we would like to introduce the MathCityMap project here.

What are the mathematical competences and contents associated with the task?

Students must estimate and/or measure, work with large numbers. The task is solved by a group – thus, communicating plays a great role and if the students explain their their solution to one another (which would be desirable), then also argue.

Has the task already been tested by students or did you receive feedback in other forms?

The task itself has been tested by students (many different classes), but still with Actionbound. The students were able to solve the problem without major (content) difficulties – with the units and number of zeros, however, it was not so good. I have only entered two-three tasks at MathCityMap to test the software. A test of the tool will be considered in spring.

The MCM team thanks for the interview and is looking forward to further tasks in Speyer!

With two trails in Salzburg, we can now welcome Austria as the 9th country with a MCM Trail. The current task of the week presents a task in the field of the surface of a cylinder. It is located in the trail at the natural sciences faculty of the Paris-Lodron University in Salzburg.

Task: Lamp (task number: 1908)

How large is the black painted surface of a lamp without the base plate? Give the result in m². Round to two decimal places.

The pupils first recognize the lamp as cylindrical and then determine the black surfaces. For this, it is necessary to divide the lamp into two cylinders. For the upper small cylinder, the shell surface as well as the cover are calculated, for the lower cylinder only the shell surface. Height and radius need to be measured. Subsequently, the individual surfaces are added and the total painted surface area is obtained.

The task can be assigned to the subject area of geometry and, in particular, geometrical bodies (cylinders) and can be used from class 9 onwards.

A popular MathCityMap task is concerned with the volume of fountains and how many liters of water are contained. The question can be used for a wide range of geometric themes, depending on the shape of the selected fountain (rectangular, circular, …). The Task of the Week is a particular challenge because the fountain has to be modeled with help of different geometric bodies.

Task: Water in the Fountain (task number: 1420)

How many liters of water are in the illustrated fountain?

The illustrated fountain can be modeled using a cuboid and a cylinder (divided into two parts). If this has been recognized, the necessary quantities must be collected and the individual volumes calculated. Finally, the conversion in liters is required. The task with cylinders can be used from class 9 onwards; simpler fountain shapes are already possible from class 6 onwards.

Depending on the structure of the well, the collection of the data can be a challenge and the students have to become creative. For example, the circumference of a circle can be helpful for the determination of the diameter. Not at least through such considerations, a flexible handling of mathematical formulas and correlations is promoted.

In this week, we are presenting a Task of the Week, which can be transferred quickly and easily to other locations. The focus of the task is the escalator with a physical question.

Task: Escalator (task number: 1805)

How fast in m / s is the escalator? Round the result by two digits.

In order to solve the problem, it is necessary to determine two values: the length of the escalator (either total or by measuring a single step and multiplying) and the duration of a ride with the escalator. It is best to take both values in the units of meters and seconds so that the speed can then be determined.

For the task, the students must know the unit m/s. Here, a connection between physics and mathematics can be recognized in the speed concept. The task can be used from class 8 onwards.

The determination of the weight of an object has often been part of a Task of the Week. However, today’s task is a particular challenge because the object consists of different materials with different densities.

Task: Bench (task number: 1803)

There are benches in front of the H7. How much does a bench seat weigh when the wood weighs 690 kg per m³ and the concrete weighs 2400 kg per m³? Give the result in kg.

The best way to solve this problem is by dividing the bench into three parts: the two concrete feet, the concrete seat and the wooden seat. A cuboid can be used as a model for all parts. Then the students take the necessary measurements and calculate the weight of concrete and wood first separately. The total weight of the bench is then calculated by addition.

The task requires knowledge about the cuboid as well as its volume. In addition, the concept of density should be known to the pupils. Within solving this task, this can be sharpened. The task is recommended from class 7.

Category: Task of the Week

Task of the Week: Arched Greenhouse

Task of the Week: Height of the Building

Task of the Week: Red Area

Task of the Week: Tafelberg’s Monument

Task of the Week: Brick in the Wall

Task of the Week: Jacobean Pilgrim

Task of the Week: Lamp

Task of the Week: Water in the Fountain

Task of the Week: Escalator

Task of the Week: Bench