When you are solving an addition calculation with a two-digit number, you need to think about tens and ones. A place value chart can help you to see the value of each digit in a number. For example, ...

There are many different types of numbers, some of which you may remember from school: natural, rational, irrational, imaginary, calculable and incalculable numbers. Today, however, we are going to ...

Subtracting larger numbers in your head is not always easy, so you can use the column method to take one number away from another. You write the larger number above the smaller number, so that the ...