Select the option that is related to the fifth letter-cluster in the same way as the second letter-cluster is related to the first letter-cluster and the fourth letter-cluster is related to the third letter-cluster. WEL: DVO :: FOR: ULI :: SDX:?
- (a)HWC
- (b)GXC
- (c)HXC
- (d)GWC
Answer
Why
Correct — A. Rule: every letter is replaced by its opposite in the alphabet, so a letter at position n becomes the letter at position 27 − n. A pairs with Z, B with Y, and so on.
WEL to DVO: W(23) becomes 27 − 23 = 4 = D, E(5) becomes 22 = V, L(12) becomes 15 = O.
FOR to ULI: F(6) becomes 21 = U, O(15) becomes 12 = L, R(18) becomes 9 = I.
Apply the same to SDX: S(19) becomes 27 − 19 = 8 = H, D(4) becomes 23 = W, X(24) becomes 3 = C.
That gives HWC, option (a).
Why the others are wrong
- (b)GXC — GXC shifts the first two letters by one. The opposite of S is H(8), not G(7), and the opposite of D is W(23), not X(24), so only the final C survives.
- (c)HXC — HXC gets S and X right but pairs D with X. D is the fourth letter from the start, so its opposite is the fourth from the end, which is W — X is only third from the end.
- (d)GWC — GWC pairs S with G. Count it out: S is the eighth letter from the end, so its opposite is the eighth from the start, H(8), and G(7) is one short.
Concept
Opposite-letter pairing has an arithmetic you can write in one line: a letter and its opposite always sum to 27. A is 1 and Z is 26, B is 2 and Y is 25, and it holds right through to M and N in the middle.
Learn them as pairs rather than as a subtraction to perform under time pressure: AZ, BY, CX, DW, EV, FU, GT, HS, IR, JQ, KP, LO, MN.
The double analogy — two worked pairs printed before the question — is there so that you can confirm the rule instead of guessing it. Test the second pair before applying anything to the third.
The four options differ only in their first two letters, H or G and W or X. The whole item therefore turns on knowing that D pairs with W and S pairs with H.
Key facts
- Opposite letters sum to 27, so A goes with Z, B with Y and M with N.
- S(19) pairs with H(8) because 19 + 8 = 27.
- D(4) pairs with W(23), and X(24) pairs with C(3).
- The pairing is symmetric, so the same rule carries DVO back to WEL.
Study next
Common traps
- Subtracting from 26 instead of 27, which moves every letter by one place
- Applying the rule to the first analogy only and assuming the second agrees
- Counting positions from the wrong end once the letter sits past M
SSC gives two worked analogies and a third to complete, which lets you confirm the rule before applying it.
The same frame appears at 09 Sep 2024, 16:00, Reasoning Q.1, where the letters are subtracted from 29 rather than 27, and at 11 Sep 2024, 09:00, Reasoning Q.7, where the rule is a growing +1, +2, +3, +4 shift.
Related PYQs
No directly related past PYQ was found.