A square piece of paper has a dot in its top right corner and is lying on a table. The square is folded along its diagonal, then rotated 90∘ clockwise about its centre, and then finally unfolded, as shown.
A number or a short expression. Fractions can be typed as 3/2, and spacing doesn't matter.
Solution
We draw an unshaded dot to represent the location of the dot when it is on the other side of the sheet of paper being shown. Therefore, the dot moves as follows:
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