Pressing "New" will generate a new wall of numbers. You can verify your calculations with the "Check"-Button.
- Immediate verification of results
You get immediate feedback whether you calculated correctly or not: the background of the field in question will be colored red if the result is not correct.
- Calculation with positive and negative numbers
You may choose to calculate not only with positive numbers but with negative ones as well (what's called "whole numbers"):
7+(-9)=-2 or 3⋅(-7)=-21 - Fractional calculus
Add fractions:
3/7+4/5=(15+28)/35=43/35It is not necessary to simplify a fraction (if possible) for the result to be accepted as correct. - Modular arithmetic
This means that you don't calculate with the numbers themselves but with their remainder after division by a given number (the divisor).
In fact you do it all the time: 5 hours after 10 a.m. is the 15th hour of the day or 3 p.m.; that is the remainder of 15 divided by 12.
Modular arithmetic is indicated in the Number Wall by e.g. +/17 showing in the background of an empty field. Which, in this case, means you should add remainders of numbers divided by 17 (also called "modulo 17"). Then, for example, the result of 2 + 16 is not 18 but
2 + 16 = 1 - Use help
If you don't know the result of, say, 56⋅75 or 7/12+23/45, you can get help by writing =56⋅75 and =7/12+23/45 respectively into the field in question. The result then will show up and the background of the field will be colored yellow. Perhaps you are familiar with these kinds of formulae from spreadsheets (like Excel).
