1089 Reverse Number Investigation

Children should be at least a solid level 4 or comfortable with adding and subtracting 3 digit numbers . This clever trick means children pick a 3 digit number with different digits and follow some simple steps. They reverse the number, take them away from each other and add the answer to itself but reversed. As long as they follow the steps carefully (you must always use 3 digit numbers for reversal reasons so 67 becomes 067) they should always end up with 1089. A fun investigation and good for practising addition and subtraction with whatever methods you or they prefer. Some extra extension challenges are provided. The sheet gives the steps and instructions.