The KBruch Handbook

The KBruch Handbook

Sebastian Stein

Anne-Marie Mahfouf

Revision 4.2 (2009-02-03)

KBruch is a small program to practice calculating with fractions and percentages. Different exercises are provided for this purpose and you can use the learning mode to practice with fractions. The program checks the user's input and gives feedback.


Chapter 1. Introduction

Chapter 1. Introduction

KBruch is a small program to practice calculating with fractions and percentages. Five different exercises are offered as well as a learning mode.

  • Arithmetic - in this exercise you have to solve a given fraction task. You have to enter the numerator and the denominator. This is the main exercise.

  • Comparison - in this exercise you have to compare the size of 2 given fractions, using the symbols >, < or =.

  • Conversion - in this exercise you have to convert a given number into a fraction.

  • Factorization - in this exercise you have to factorize a given number into its prime factors.

  • Percentage - in this exercise you have to calculate percentages.

In each different exercise KBruch will generate a task and the user has to solve it. The program checks the input and gives a feedback about it.

KBruch counts how many tasks were solved at all and how many tasks were solved correctly. The statistics are shown to the user.

KBruch is very compact and focuses on the core idea of a task generator. An online help system provides context-sensitive help for the different situations.

Chapter 2. Using KBruch

Chapter 2. Using KBruch

Choosing the mode: learning or exercises

When you start KBruch, it offers you two modes: Freestyle which is the training mode and Learning where you can understand fractions. Clicking one of the pictures will enter the chosen mode. Here is a screenshot of KBruch's mode choices:


KBruch mode choices

Click one of the picture to choose the mode.

Main freestyle screen

Main freestyle screen

Here is a screenshot of KBruch's main freestyle screen:


KBruch main screen

All exercises take place in this screen. This ensures that KBruch is easy to use even for young users! The main screen is separated into 5 parts:

  • the menubar with the 3 menus File, Settings and Help

  • the toolbar, where you can switch between the different exercises

  • the Options on the left, where you can define the difficulty and various settings for the tasks

  • the task part, where you have to enter the result of the given task

  • the statistical part, where you can see how many tasks have been solved correctly or attempted

At any time, you can go back to Modes using the Back icon in the toolbar.

Note

You can hide the Options section by dragging it to the left.

First you have to choose an exercise in the toolbar. Default is Arithmetic. The task part will change according to the chosen task. Some settings in the Options section will be enabled, depending on the task you have chosen.

You will find an icon to generate a new task in the toolbar as well. This action is also available in the menu File->New. This action is always enabled. If you have not solved the currently given task, a new task is generated and the statistics are set back.

If you terminate KBruch the currently chosen exercise will be saved and restored on next startup.

Statistical Part

Statistical Part


KBruch statistics

In this part of the main screen you can see:

  • on the left, how many tasks have been solved

  • on the right, in green, how many tasks have been solved correctly

  • on the right, in red, how many tasks have been solved incorrectly

  • on the right, in orange, how many tasks have been skipped

You can reset the statistics by clicking on the New button in the toolbar or choosing File->New in the menubar.

The statistics will be saved when KBruch is closed and restored on next startup.

Configuring KBruch appearance

Configuring KBruch appearance

In this dialog you can adjust some general settings for the task display. To open this dialog use Settings->Configure KBruch.


KBruch settings dialog

There are two tabs to adjust the setting:

  • Colors: Choose the colors for the different parts of a mathematical expression: numbers, operational sign, fraction bar.

  • Fonts: Choose a font for displaying the task.

The settings will be saved on KBruch's termination and restored on the next startup.

Main learning screen

Main learning screen


KBruch learning mode

Clicking the Hint button toggles the display of the help on the right which explains you how the rings work.

Chapter 3. Exercises

Chapter 3. Exercises

Exercise Arithmetic

In this exercise you have to solve a given task. Therefore you have to enter the integer part of a fraction and the numerator and the denominator. The difficulty of the generated task can be adjusted by using some options on the left.

Options

There are several parameters which influence the difficulty of the generated tasks:

Question

Mixed number

Set if the fractions will appear as mixed numbers or not in the question expression ( mixed number example: 1 4/5 = 9/5 ).

Number of terms

The number of terms (separate fractions) given in each task. From 2 to 5, inclusive.

Maximum denominator

The highest number KBruch will use as the main denominator in the tasks it sets. From a minimum of 10 to a maximum of 50.

Answer

Mixed number

Set if the fractions will appear as mixed numbers or not in the answer ( mixed number example: 1 4/5 = 9/5 ).

Reduced Form

Check this to force the use of the reduced form.

Solution

Mixed number

Set if the fractions will appear as mixed numbers or not in the solution ( mixed number example: 1 4/5 = 9/5 ).

Operations

Operations which should be used in the task: Addition, Subtraction, Multiplication or Division. Check all operations you want to use.

After you have changed the parameters you have to click on the New button in the toolbar to generate a task which uses the new parameters. You can also call this action from the menubar with Task->New. This will reset the statistics. To avoid that, click the Next button to proceed with the changed parameters.

The chosen parameters will be saved on KBruch's termination and restored on next startup.

Solving Tasks

After you have solved a given task, you need to enter the result into the three input boxes. In the left box you enter the integer part of the fraction, in the upper box the numerator and in the lower box the denominator. If the option Mixed number in the Answer section is unchecked, the left box for the integer part of the fraction is hidden. Then you use only the numerator box and the denominator box for your input.

If the result is negative, you can enter a minus sign in front of the numerator or denominator. If the result is 0, just type a 0 in the numerator input field. If the result has a denominator of 1, you can leave the lower box empty.

After you have entered the result you should click the Check button below the input boxes. KBruch will check your input and present the correct result on the right below the Incorrect! string:


Checked Task

This task was solved incorrectly. The correct value is shown in 2 different forms: normal (reduced) and mixed number.

Note

If you checked the Reduced form in the Options in the Answers section then you always have to enter the result reduced. KBruch will show you a short message like the one in the screenshot below, if you enter the correct result unreduced. The answer will then be counted as incorrect.


Unreduced Result

To continue with the next task, click on the Next button. If you want to change the parameters for the next task please do this before clicking on the Next button.

Exercise Comparison

Exercise Comparison

In this exercise you have to compare 2 given fractions. You have to choose the bigger fraction of both by selecting the correct comparison sign.


Exercise Comparison

First choose the correct comparison sign. After you have chosen the comparison sign, the result will show on the right. A green square with Correct will tell you that your answer was correct while a red square with Incorrect will indicate that your answer was wrong. You will get to the next task by clicking the Next button.

In this exercise only the option Mixed number is enabled. If checked the fractions will appear as mixed numbers.

Exercise Conversion

Exercise Conversion

In this exercise you have to convert a given number into a fraction. You have to enter numerator and denominator.


Exercise Conversion

On the left side of the equal sign in the screenshot above you can see a recurring decimal. This means, that the fraction shown as a decimal has a repeating part. The repeating part is marked with the small bar above the numbers. Those numbers repeat ad infinitum.

After you have entered the numerator and denominator click on the Check button. KBruch will check your input and present the correct result. After this step you will get to the next task by clicking on the Next button.

Note

Do not forget to enter the result reduced. Unreduced results will be counted as solved not correctly.

In this exercise all options are disabled.

Exercise Factorization

Exercise Factorization

In this exercise you have to factorize a given number into its prime factors. You have to enter all prime factors of the number.


Exercise Factorization

You can enter a factor by clicking on the prime factor buttons. The “*” sign is automatically inserted, when you click the next prime factor button. You can remove the last entered prime factor by clicking on the Backspace button.

After you have entered all prime factors click on the Check button. KBruch will check your input and present the correct result. After this step you will get to the next task by clicking on the Next button.

In the screenshot at the top of this page you can see a “*” between the prime factors. This is the multiplication sign. The product of all prime factors must be the number you try to factorize.

Note

You have to enter all prime factors even when a prime factor repeats several times. Example: As prime factors of number 18 you have to enter 2, 3 and 3.

In this exercise all options are disabled.

Exercise Percentage

Exercise Percentage

In this exercise you have to answer some percentage questions.


Exercise Percentage

After you have entered your answer click on the Check button. KBruch will check your input and present the correct result. After this step you will get to the next task by clicking on the Next button.

In this exercise all options are disabled.

Chapter 4. Credits and License

Chapter 4. Credits and License

KBruch

Program and documentation Copyright, 2001-2004 Sebastian Stein

Thank you goes to:

  • Anne-Marie Mahfouf for managing the KDE Edu project

  • Klas Kalass for helping design the interface

  • Eva Brucherseifer for writing KMath (KBruch's GUI is based on this work)

  • Dominique Devriese for bug fixing

  • Stefan Schumacher for testing a very early version

  • Sven Guckes for testing the text interface (which has been removed)

  • David Faure for helping with KDE CVS and KDE Bugzilla

  • Robert Gogolok for helping with KDE CVS

  • John Kesson for proof reading the handbook

New interface design and usability improvements for KDE 4.1:

  • Paulo Cattai

  • Danilo Balzaque

  • Roberto Cunha

  • Tadeu Araujo

  • Tiago Porangaba

This documentation is licensed under the terms of the GNU Free Documentation License.

This program is licensed under the terms of the GNU General Public License.

Appendix A. Installation

Appendix A. Installation

How to obtain KBruch

KBruch is part of the KDE project http://www.kde.org/.

KBruch can be found in the kdeedu package on ftp://ftp.kde.org/pub/kde/, the main FTP site of the KDE project.

Requirements

Requirements

In order to successfully use KBruch, you need KDE > 4.1 .

KBruch itself can be found on the KBruch home page and it is part of the KDE Edu project

You can find a list of changes in the SVN commit messages.

Compilation and Installation

Compilation and Installation

For detailed information on how to compile and install KDE applications see Building KDE4 From Source

Since KDE uses cmake you should have no trouble compiling it. Should you run into problems please report them to the KDE mailing lists.