# HippoMath

### From OLPC

**HippoMath** is an Etoys game that tests math.

Download: HippoMath.pr

## Contents |

## How do you play it?

The program creates math questions that can be made easier or harder.

Several numbers appear on screen, and one of them is the correct answer.

The player controls a blue hippo with the arrow keys or with the circle keypad (game controller).

When the hippo gets to the right answer, the next question appears.

at the bottom:
if **addsubtract = true**: there will be + and - questions, if **multiplydivide = true**: there will be x and / questions

Move the hippo with this or the keyboard arrows <- ->

## Making questions easy or difficult

In the download, HippoMath has addition (0+0 to 50+50), subtraction (0-0 to 100-50), multiplication (0x0 to 10x10), and division (1/1 to 100/10).

To change the questions, right-click on **= ?** and open the Viewer (the eye). You will see this:

In **A + B = C**, A and B are more than **addMin** and less than **addMax** (addMin < A,B < addMax)

In **A - B = C**, B and C are more than **minusMin** and less than **minusMax** (minusMin < B,C < minusMax)

In **A x B = C**, A and B are more than **factorMin** and less than **factorMax** (factorMin < A,B < factorMax)

in **A / B = C**, B and C are more than **factorMin** and less than **factorMax**. (4 / 2 = 2) (factorMin < B,C < factorMax)

When you change the questions, you should change **answerMin** and **answerMax** so the correct answer is hard to find. The other numbers on the screen are more than answerMin and less than answerMax.

## Negative Numbers and Other Changes

**Negative Numbers**

If you want to use questions with negative numbers (-10 + 5 = -5), make **addMin = -50** and **minusMin = -50** **factorMin = -10** or use other negative numbers.

**Other Changes**

If you want to make changes to the program, I am sorry but it is not easy. The code is sometimes too big to read on the screen. Be careful if you make changes.

## Download

## Need Help?

**If you have questions or suggestions for the next version, please ask.**