Question 11
MediumOriginal questionFind the mirror image of the grid, with its 8 shaded squares, when the mirror is held vertically along the line MN to its right.
Show the answer and explanation
Correct answer: A
Explanation
A mirror standing along MN, to the right of the grid, swaps left and right but not top and bottom: a square in column c moves to column and stays in its row.
So the shaded squares (1, 2), (1, 3), (2, 1), (2, 2), (2, 3), (3, 1), (3, 2), (4, 2) (row, column) move to (1, 3), (1, 4), (2, 3), (2, 4), (2, 5), (3, 4), (3, 5), (4, 4).
Figure 1 shows exactly these squares.
Worth noting
Figure 2 is the water image (top and bottom swapped), Figure 3 is the grid turned upside down, and Figure 4 is the grid given a quarter turn. A mirror never turns a figure; it only flips it.
- Concept
- Mirror image in a vertical mirror
- Typical timeTypical
- 70 s
- Your timeYours
- —
Ten questions from Non-verbal Reasoning, at your own pace.