Sometimes, you may find it helpful to know a rough answer to a sum. You may be in a shop, and want to know broadly what you’re going to have to pay. You may need to know roughly how much money you need to meet a couple of bills. You may also want to know roughly what the right answer to a more complicated calculation is likely to be, to check that your detailed work is correct. Task: Use the label tool or the text tool to demonstrate how you can use rounding to solve an addition problem and a subtraction problem. Use the voice recording tool to explain what is happening.