Select the correct mirror image of the given figure when the mirror is placed at MN as shown below.

- (a)

- (b)

- (c)

- (d)

Answer
Why
Correct — C. Rule: a mirror on a vertical line reverses left and right — the last character becomes the first, and every character is itself turned back-to-front.
The strip reads 6 k 4 R p 2, and MN stands vertically at its right-hand end.
The image must therefore run 2, p, R, 4, k, 6 from left to right, with every glyph laterally inverted: a backwards 2, a p facing the other way, a reversed R, a reversed 4, a reversed k and a reversed 6.
Option (c) is the only strip that does all of that. Flip it back left-to-right and it restores 6 k 4 R p 2 exactly.
Why the others are wrong
- (a)The order is right, but the R stands upright instead of reversed. A mirror inverts every character, letters and digits alike.
- (b)The 4 and the k are flipped top-to-bottom, not left-to-right. Flip this strip back across MN and those two return upside-down instead of restoring 4 and k, so it is not the mirror image.
- (d)The left-hand end is wrong: p and 2 appear upright and in their original order, where the image needs a reversed 2 followed by a reversed p.
Concept
A mirror placed on a vertical line MN performs a lateral inversion. The order of the characters reverses, and each character is separately flipped about its own vertical axis.
Both halves have to happen. Options that reverse the order but leave one character standing the right way round are the standard trap, and at thumbnail size they are genuinely hard to see.
The quick check is to flip the option back in your head and read it. If the result is the original strip in the original order, that option is the mirror image.
MN is drawn as a plain vertical bar to the right of the strip, so the reflection is a straight left-right flip with no rotation involved.
Key facts
- A mirror on a vertical line reverses left-right order and flips each character laterally.
- The stem strip is 6 k 4 R p 2, with the mirror MN vertical at its right-hand end.
- The correct image reads, left to right, a reversed 2, p, R, 4, k and 6.
- Flipping the correct option back horizontally reproduces the stem unchanged.
Study next
Common traps
- Checking the order of the characters and forgetting each character's own orientation
- Flipping a glyph top-to-bottom, which is a water image, when the mirror line MN is vertical
- Settling for a strip at thumbnail size, where a single unreversed R is easy to miss
Mirror-at-MN items are asked at 11 Sep 2024, 12:30, Reasoning Q.10 and at 10 Sep 2024, 12:30, Reasoning Q.8, both presented as picture options with no text.
Related PYQs
No directly related past PYQ was found.