In the following diagram, the 'rhombus' stands for 'teachers', the 'circle' stands for 'social servants', and the 'pentagon' stands for 'females'. [Image: numbers 20, 15, 9, 24, 10, 30]
How many female teachers are also social servants?
The sequence of folding a piece of paper and the manner in which the folded paper has been cut is shown in the following figures. How would this paper look when unfolded? [Image]
Select the number-triad in which the three numbers share a different relationship from that shared by the three numbers in the rest of the number-triads.