Double

 The double of a number or an amount is twice that number or amount

 

How to double a number:

• add the number to itself,  e.g.  6 + 6 =12

• multiply the number by 2, e.g. 2 x 6 = 12

Example:
the double of 3 is 6, because

           

               3 + 3 = 6     

       or     2 x 3 = 6

 

  Practice in doubles here : https://ictgames.com/mobilePage/archeryDoubles/index.html

 

Doubles and non-doubles

Any number that can not be obtained by doubling a whole number, is a non-double number

For example: 

 8 is the double of 4,  but

9, 7, 15,  etc. are non-double numbers