1. Enter two double-digit numbers that are to be added together into the provided boxes.[br]2. Move the slider so that the two pictorial representations overlap.[br]3. If any of the shaded regions overlap, then there will need to be a carry. Move the units slider, if required, to carry 10 ones over to the tens columns. Move the tens slider, if required, to carry 10 tens over as a hundred.[br]4. Click the 'Reset' button to restart the process.