Knowing the doubles of single digit numbers is a powerful mental arithmetic tool and one strongly emphasised by the Primary Framework for maths. Once the doubles have been learned it is a short step to being able to work out the halves of even numbers up to 20. These two worksheets put a slightly different slant on knowing doubles by asking questions such as: 'If I halve my number the answer is 6. What is my number?' A child with the knowledge that doubling is the opposite of halving can look at this question and see that it is the same as asking what double 6 is. Easy! Go to our Word problems on doubling and halving for Year 2