
Copyright © 2001-2005 Sebastian Stein
Copyright © 2008 Anne-Marie Mahfouf
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.

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.

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:

Click one of the picture to choose the mode.

Here is a screenshot of KBruch's main freestyle 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 , and
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
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 ->. 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.


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 button in the toolbar or choosing -> in the menubar.
The statistics will be saved when KBruch is closed and restored on next startup.

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

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.

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.
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 button in the toolbar to generate a task which uses the new parameters. You can also call this action from the menubar with ->. This will reset the statistics. To avoid that, click the button to proceed with the changed parameters.
The chosen parameters will be saved on KBruch's termination and restored on next startup.
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 button below the input boxes. KBruch will check your input and present the correct result on the right below the Incorrect! string:

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

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

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.

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

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

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 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 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.

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

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 button.
After you have entered all prime factors click on the 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 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.

In this exercise you have to answer some percentage questions.

After you have entered your answer click on the 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 button.
In this exercise all options are disabled.

KBruch
Program and documentation Copyright, 2001-2004 Sebastian Stein
(seb.kde AT hpfsc.de)
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
(paulo.cattai AT ltia.fc.unesp.br)
Danilo Balzaque
(danilo.balzaque AT ltia.fc.unesp.br)
Roberto Cunha
(roberto.cunha AT ltia.fc.unesp.br)
Tadeu Araujo
(tadeu.araujo AT ltia.fc.unesp.br)
Tiago Porangaba
(tiago.porangaba AT ltia.fc.unesp.br)
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.

Table of Contents
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.

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.

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.