SSC CGL 2024 Tier-I · 23 September 2024, Shift 1 · General Intelligence and Reasoning · Question 4 of 97

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.

Select the number that will come in the place of the question mark(?), if ‘+’ and ‘ – ‘ are interchanged and ‘×’ and ‘÷’ are interchanged 63 × 7 ÷ 13 – 64 + 42 = ?

(a)139
(b)131
(c)144
(d)124

Answer

Why

Correct — A. Swap the symbols on paper first, then apply BODMAS to the line you have written.

Swap + with − throughout, and swap × with ÷ throughout.

So 63 × 7 ÷ 13 − 64 + 42 rewrites as 63 ÷ 7 × 13 + 64 − 42.

63 ÷ 7 = 9
9 × 13 = 117
117 + 64 = 181
181 − 42 = 139 → option (a)

Why the others are wrong

(b)
131 — 131 is eight short. The division-and-multiplication block is fixed at 63 ÷ 7 × 13 = 117, and 117 + 64 − 42 offers no route to 131.
(c)
144 — 144 is five over. It would need the first block to reach 122, but 63 ÷ 7 = 9 and 9 × 13 = 117, and the + 64 − 42 tail is fixed.
(d)
124 — 124 is fifteen short. Leaving the symbols unswapped gives 441 ÷ 13 − 64 + 42, which is not even a whole number — a sign the swap was skipped.

Concept

Symbol-interchange items test two things at once: whether you rewrite before you calculate, and whether you then respect order of operations.

The swap is on the printed symbols only. Numbers stay where they are. Once the new line is written, it is ordinary arithmetic — division and multiplication left to right, then addition and subtraction.

A useful self-check: SSC builds these so the swapped line divides cleanly. If your working throws up a fraction, you have almost certainly calculated on the printed line instead of the swapped one.

Key facts

Rewrite the expression with the symbols swapped before any arithmetic is done.
BODMAS applies to the rewritten line, never to the printed one.
The rewritten line is 63 ÷ 7 × 13 + 64 − 42, which equals 139.

Study next

Symbol-interchange items where only one pair of symbols is swappedLeft-to-right order when division comes before multiplicationWhich-two-signs-should-be-interchanged items, the same idea run backwards

Common traps

Applying BODMAS to the printed line and swapping afterwards.
Swapping only one of the two pairs named in the instruction.
Reading 63 ÷ 7 × 13 as 63 ÷ 91 by doing the multiplication first.

The same double swap — + with −, × with ÷ — is set at 10 Sep 2024, 16:00, Reasoning Q.24 (11 ÷ 12 − 78 × 6 + 57) and at 09 Sep 2024, 09:00, Reasoning Q.8 (5 − 4 ÷ 9 + 80 × 10).

Related PYQs

No directly related past PYQ was found.