Multiplication is often thought of as repeated addition. By building a times table by using a repeated addition rule you will have a fun practice of the multiplication facts, and you will learn to build rules in spreadsheets. Rules let you program spreadsheets to do remarkable things like make the multiplication table in just a couple of easy steps.
Tag: addition and subtraction
Place Value: Thousands
We extend the place value generator to 100’s of thousands to show you how the pattern of 1’s, 10’s, 100’s, continues to 1,000’s, 10,000’s, 100,000’s. Enter numbers and watch the expanded and compact forms of place value change. Pay special attention to using text units and take a look at the rule we used to add those units to the number while letting the number change.
Place Value: Decimals
We take our place value generator to decimals to help students see the simplicity of the place value pattern going right as well as left.
Place Value
Our number system inherited from India and from the Medieval Arab world enables us to use just 10 symbols to write any number we can imagine. Students learn in this spreadsheet to enter numbers, to compare compact and expanded forms of those symbols and to add units to any number. Students who like to explore further can extend the place values from 3 digits to more and learn the trick that lets them include any kind of text with numbers they can change.
More Number Lines
We use rules to build new numberlines. For example we can start in the middle and go both forward or backward using adding and subtracting rules. You can even generate and experiment with negative numbers by subtracting below 0. As you build numberlines on spreadsheets you are building them in your mind. And by thinking of numberlines in terms of rules you are getting ready for algebra.