SSC CGL 2024 Tier-I · 17 September 2024, Shift 3 · General Intelligence and Reasoning · Question 25 of 98

Text as printed on a candidate's response sheet for this shift; answer per SSC's tentative key as marked on that sheet. Solution last reviewed 6 September 2026.

Where this paper and its answers come from

SSC does not publish CGL question papers or a public answer key. The questions and options here are reproduced as printed on a candidate's own response sheet for this shift — the Commission's text, unchanged. Each answer is SSC's tentative key as marked on that sheet; SSC allowed challenges to it and never publishes a final key. The solutions are written by UnlockIAS.

What will come in place of ‘?’ in the following equation, if ‘+’ and ‘–‘ are interchanged and ‘×’ and ‘÷’ are interchanged? 6 ÷ 8 – 91 × 13 + 30= ?

(a)20
(b)25
(c)22
(d)23

Answer

Why

Correct — B. Rewrite the line with the symbols swapped, then apply BODMAS to the new line.

Given: 6 ÷ 8 − 91 × 13 + 30
Swapped: 6 × 8 + 91 ÷ 13 − 30

6 × 8 = 48
91 ÷ 13 = 7 (13 × 7 = 91)
48 + 7 = 55
55 − 30 = 25 → option (b).

Why the others are wrong

(a)
20 — 20 needs 48 + 7 to come to 50. Those two terms make 55, and 55 − 30 = 25.
(c)
22 — 22 needs 91 ÷ 13 to be 4. The quotient is 7, because 13 × 7 = 91.
(d)
23 — 23 needs 6 × 8 to read 46. The product is 48.

Concept

Interchange questions are marked on care rather than on arithmetic. The numbers are kept small on purpose.

Rewrite the whole line with the swapped symbols before you calculate anything. Reading the swap while you compute is what produces the near-miss answers the options are built from.

Then run BODMAS on the rewritten line. The multiplication 6 × 8 and the division 91 ÷ 13 are both settled before the addition and the subtraction, whatever order they are printed in.

Both swaps matter. Exchanging only the multiplication and division signs leaves 6 × 8 − 91 ÷ 13 + 30 = 71, which is not offered — the sign that a step was skipped rather than an arithmetic slip made.

Key facts

After the swap the line reads 6 × 8 + 91 ÷ 13 − 30.
91 ÷ 13 = 7, since 13 × 7 = 91.
48 + 7 − 30 = 25.

Study next

Interchange items where the swap turns an awkward division into an exact one, as 91 ÷ 13 does hereBODMAS on a rewritten line whose printed order tempts you to work left to rightInterchange items that exchange two of the numbers as well as the symbols

Common traps

Swapping only one of the two pairs of symbols.
Working left to right after the swap, which folds the subtraction into the division.
Rounding 91 ÷ 13 instead of checking that 13 divides 91 exactly.

The identical stem, with the same two swaps on larger numbers, is set at Reasoning Q.17 of this shift. The method carries over unchanged: rewrite the line first, then apply BODMAS.

Related PYQs

No directly related past PYQ was found.