The first pair of numbers (-5mm, -3mm) relate to the maxilla, and the second pair (-3mm, -4.5mm) to the mandible. Each number represents the space available for the future eruption of permanent teeth, meaning that there is a deficit of space in each quadrant. For the maxilla, the total space deficit is -5mm + -3mm = -8mm. So, the actual space loss in the maxilla is 8mm. For the mandible, the space deficit is -3mm + -4.5mm = -7.5mm. Therefore, the actual space loss in the mandible is 7.5mm.