As children get older the numbers they work with get larger and by year 3 onwards they start using written methods to work out answers. Later they also use calculators and it is worth remembering that one of the two SAT Papers in Year 6 is a calculator paper. With this development come new challenges: being able to calculate a rough answer very quickly and being able to check an answer by doing a different calculation. This set of worksheets looks at the second of these in relation to addition and subtraction. The first two pages look at checking subtraction by carrying out an addition. The third page looks at carrying out addition in a different order to check answers. Both these skills are important and should not be neglected. Go to Checking Answers