Young Einstein Mathematics Educational Software Contents

Activity Number 19

Heading : Subtracting 10s

Description : Subtracting two numbers each being multiples of 10

Aim/Questions : Perform the subtraction.

Educational software theory used:

Subtracting 10s

When subtracting tens you just need to remember that it is the same process as subtracting ones, but this time they are in the tens columns.

When you write the answer make sure that you include the ones column, even though it is zero.

Eg

 60 - 20 =

Simply subtract the tens units 6 - 2 to get 4

 6  - 2  = 4

But since they are tens and not ones units remember to add the trailing zero so that we know they are tens.

         = 40

Educational software Instruction :

1.  Add the two numbers together then type your answer into the ‘Answer Box’ provided.

2.  Press ‘Enter’ when you have finished.

Click on the ‘Wording’ check box if you want the sum written in a sentence.

It might be easier to have backwards entry enabled for this exercise.

Module 19. These Instructions from 'Young Einstein Mathematics educational software by Maths Practice are Copyright. Copyright Maths Practice P/L 2003 ©