SSC CGL 2025 Tier-I · 16 September 2025, Shift 1 · General Intelligence and Reasoning · Question 25 of 100

We transcribed this text from the pictures on a candidate's response sheet for this shift; the answer is the key SSC colour-marked on that sheet. Solution last reviewed 13 September 2026.

Where this paper and its answers come from

SSC does not publish CGL question papers or a public answer key. From 2025 the candidate response sheet prints every question and option as a picture, so the text here is transcribed from those pictures for this shift and checked against them independently; where the layout carries meaning, the picture is shown as well. Each answer is the key SSC colour-marked 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. The solutions are written by UnlockIAS.

The ratio of two numbers is 4:5 and their sum is 180. Find the numbers.

(a)60 and 75
(b)72 and 108
(c)80 and 100
(d)64 and 116

Answer

Why

Correct — C.
Rule: split the sum into the ratio's parts.

Total parts: 4 + 5 = 9
One part: 180 ÷ 9 = 20
Numbers: 4 × 20 = 80 and 5 × 20 = 100

Check: 80 + 100 = 180 ✓ → option (c).

Why the others are wrong

(a)
60 and 75 — 60 and 75 are in the ratio 4 : 5 (4 × 15 and 5 × 15), but their sum is 135, not 180.
(b)
72 and 108 — 72 and 108 add to 180, but 72 : 108 = 2 : 3, not 4 : 5.
(d)
64 and 116 — 64 and 116 add to 180, but 64 : 116 = 16 : 29, not 4 : 5.

Concept

A ratio 4 : 5 means the numbers are 4k and 5k for one common multiplier k. Their sum is 9k.

So divide the sum by the total number of parts to get k, then multiply back: k = 180 ÷ 9 = 20.

An answer must pass both conditions, the ratio and the sum. Options (b) and (d) match the sum only, and option (a) matches the ratio only.

Key facts

For a ratio a : b with sum S, one part = S ÷ (a + b).
Here one part = 180 ÷ 9 = 20.
60 : 75 also reduces to 4 : 5, so a ratio alone does not fix the numbers.

Study next

Dividing an amount in a three-term ratioRatio problems given the difference instead of the sumCombining pairwise ratios such as P : Q and Q : R into P : Q : R

Common traps

Picking the first option in the right ratio without checking the sum
Dividing 180 by 4 or 5 instead of by the total parts, 9

The same frame is keyed at 12 Sep 2025, 16:00, Reasoning Q.18: ratio 3 : 5 with sum 64 gives 8 parts of 8, so the numbers are 24 and 40.

Related PYQs

No directly related past PYQ was found.