1. Sam seemed to be digging up his square tiled patio when I dropped in on him yesterday. “No, only making it smaller,” he told me. “I’m removing the outer tile all the way round. That’s taking away one tile less than the total that will remain.” The tiles were square and all the same size, so how many would he be removing?

40 tiles to be removed

32 tiles to be removed

24 tiles to be removed