SSC CGL 2024 Tier-I · 13 September 2024, Shift 1 · General Intelligence and Reasoning · Question 2 of 100

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 10 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.

Which of the following interchanges of numbers (not digits) would make the given equation correct?

(a)5 and 9
(b)0.3 and 1.6
(c)27 and 480
(d)500 and 190

Answer

Why

Correct — B. The equation in the figure is (480 ÷ 0.3 × 5 + 500) over (190 + 9 × 27 ÷ 1.6) = 2, and the stem allows you to swap whole numbers, not digits.

Swap 0.3 and 1.6, then work each line by BODMAS, taking × and ÷ left to right.

Numerator: 480 ÷ 1.6 = 300
300 × 5 = 1500
1500 + 500 = 2000

Denominator: 9 × 27 = 243
243 ÷ 0.3 = 810
810 + 190 = 1000

2000 ⁄ 1000 = 2, exactly what the equation claims — option (b).

Why the others are wrong

(a)
5 and 9 — Swapping 5 and 9 gives a top of 480 ÷ 0.3 × 9 + 500 = 14,900 and a bottom of 190 + 5 × 27 ÷ 1.6 = 274.375. That ratio is about 54, nowhere near 2.
(c)
27 and 480 — Swapping 27 and 480 shrinks the top to 27 ÷ 0.3 × 5 + 500 = 950 and inflates the bottom to 190 + 9 × 480 ÷ 1.6 = 2,890, a ratio of about 0.33.
(d)
500 and 190 — Swapping 500 and 190 touches neither division, so the top becomes 480 ÷ 0.3 × 5 + 190 = 8,190 and the bottom 651.875. That is about 12.6, not 2.

Concept

This family turns on BODMAS plus the rider numbers, not digits.

Numbers, not digits means 0.3 may move as a whole to where 1.6 stands. It does not let you split 27 into 2 and 7, or read 480 as 048.

Order then decides everything. The numerator is where it bites: 480 ÷ 1.6 × 5 read left to right is 300 × 5 = 1500, while 480 ÷ (1.6 × 5) would be 60. SSC does not bracket it, so left to right is the rule.

A swap has to be tested above and below the bar. Three of the four options change only one side meaningfully, and a candidate who checks the numerator alone can convince himself too early.

Key facts

Under BODMAS, × and ÷ rank equally and are worked left to right, as are + and −.
480 ÷ 1.6 = 300 and 9 × 27 ÷ 0.3 = 810 are the two lines the correct swap turns on.
After the swap the equation reads 2000 ⁄ 1000, which is the 2 the question asserts.

Study next

BODMAS with of, and why of is settled before divisionInterchange-of-signs questions where + and − or × and ÷ trade placesFraction equations where a candidate swap must be checked on both halves

Common traps

Interchanging digits instead of whole numbers, which the stem forbids
Reading 480 ÷ 0.3 × 5 as 480 ÷ (0.3 × 5)
Testing only the numerator and stopping once it looks tidy

SSC prints either a swap of numbers or a swap of operators. The operator version appears in this shift at Reasoning Q.19, where + and − and then × and ÷ trade places before the equation is solved.

Related PYQs

No directly related past PYQ was found.