I think the images should make sense. If not, just comment, I’ll be here. (It’s only letting me insert one image so I’ll have to exp this part) once you’ve filled the two way table in, you circle the two squares that Apple to the situation. In this case, which ones don’t have a brother? The top right and bottom right fit that bill. Then you divide the number of students that actually have a sister but the two squares (added together) that do t have a brother. So it’d be 5/10 which is .5 for an answer
