SSC CGL 2025 Tier-II · Paper-I, 19 January 2026 · Reasoning and General Intelligence · Question 1 of 150

We transcribed this text from the pictures of a candidate's response sheet for this paper; the answer is the key SSC marked with a green tick on that sheet. Solution last reviewed 11 September 2026.

Where this paper and its answers come from

SSC does not publish CGL question papers or a public answer key. This paper reaches us as a candidate's response sheet saved as pictures, so we transcribed the text from those pictures, and a second reader checked every question against them; where the layout carries meaning, we show the picture too. Each answer is the key SSC marked with a green tick on that sheet. SSC released a tentative key for challenge and later its final one, both only to candidates behind a login, and the sheet does not say which of the two it carries. UnlockIAS wrote the solutions.

If P denotes '+, Q means '÷', R means ‘−’ and S means ‘×’, then which of the following equations is correct?

(a)16 S 5 R 10 P 4 Q 3 = 9
(b)16 P 5 R 10 S 4 Q 3 = 19
(c)16 Q 5 P 10 S 4 R 3 = 12
(d)16 S 5 Q 10 P 4 R 3 = 9

Answer

Why

Correct — D.
Rule: turn each letter into its sign, then do × and ÷ before + and − (BODMAS).

16 S 5 Q 10 P 4 R 3
= 16 × 5 ÷ 10 + 4 − 3
= 80 ÷ 10 + 4 − 3
= 8 + 4 − 3 = 9 → option (d).

Why the others are wrong

(a)
16 S 5 R 10 P 4 Q 3 = 9 — 16 × 5 − 10 + 4 ÷ 3 = 80 − 10 + 1⅓ = 71⅓, not 9. It is the keyed equation with Q and R exchanged, so it reaches 9 only if R means ÷ and Q means −.
(b)
16 P 5 R 10 S 4 Q 3 = 19 — 16 + 5 − 10 × 4 ÷ 3: the product and quotient go first, 40 ÷ 3 = 13⅓, so the value is 21 − 13⅓ = 7⅔, not 19.
(c)
16 Q 5 P 10 S 4 R 3 = 12 — 16 ÷ 5 + 10 × 4 − 3 = 3.2 + 40 − 3 = 40.2, nowhere near 12.

Concept

A symbol-substitution item takes two steps. First rewrite the equation with the real signs, then evaluate it by BODMAS: × and ÷ first, working left to right, then + and −.

Rewrite all four options before judging any. Three of them here do not even come out whole: 71⅓, 7⅔ and 40.2.

Option (a) is option (d) with Q and R exchanged. Mix up those two letters and (a) comes to 9 while (d) does not, which is why the code has to be applied letter by letter.

Key facts

P = +, Q = ÷, R = − and S = × in this item.
BODMAS: division and multiplication before addition and subtraction, each worked left to right.
16 × 5 ÷ 10 = 8, and 8 + 4 − 3 = 9.

Study next

Sign-swap items where one operator stands for another, such as '+' meaning ÷Interchanging two numbers or two signs to balance an equationCoded expressions with brackets, evaluated by BODMAS

Common traps

Swapping the meanings of Q and R, which makes option (a) come to 9
Reading a letter as the sign it begins, such as S for subtraction, when here S means ×

19 Jan 2026, 11:00 AM, Reasoning Q.17 recodes the signs themselves ('+' means division) and asks for a value: 36 − 2 + 4 × 10 ÷ 5 becomes 36 × 2 ÷ 4 + 10 − 5 = 23.

At 17 Sep 2025, 16:00, Reasoning Q.6 letters stand for the signs as they do here, with P for addition, and a bracketed expression works out to 7.

Related PYQs

No directly related past PYQ was found.