CSIR NET December 2025 — Part A — General Aptitude

Five students graduated from a college, not all in the same year, after each has studied for four years. If batchmates Jiten and Anwar were between Ramesh and Prakash but senior to Sam while Ramesh had left the college before Jiten took admission, then it is certain that

Which among the following cities can be said most appropriately to bear the same relation to Tamil Nadu that Pune bears to Maharashtra; Surat to Gujarat and Asansol to West Bengal?

The geometric mean of 100 observations is 25. If each observation is multiplied by 4, what will be the new geometric mean?

Alloy A is formed by mixing iron (Fe) and nickel (Ni) in the ratio 3:4, while alloy B is formed by mixing Fe and Ni in the ratio 9:5. If equal quantities of alloys A and B are melted together to form a new alloy C, what will be the ratio of Fe to Ni in alloy C?

Two identical metal bars are heated to different temperatures and allowed to cool in the same surroundings. Which one of the following figures correctly shows their cooling curves?

The following figure shows densities and masses of five objects (A to E) on a radar chart, with density and mass each read on the same 0–5 scale along its own spoke. The object with the largest volume is ____.

In an exam, questions of three difficulty levels — hard, medium, and easy — fetch respectively 7, 3, and 2 marks if correct and 0 if incorrect. Three students got 30 marks each but in three different ways, though the total number of questions correctly answered by each student was the same. Then what could be the total number of questions correctly answered by each of these students?

The following plot shows temperature as a function of x and y, brightest at the far corner (x, y) = (5, 5) and darkest at the origin, with the colour banding curving between them rather than running in straight stripes. Along which path is the temperature change minimum?

The minimum height of a plane vertical mirror that will allow a 6-feet tall person to see himself fully in it

Three periodic events repeat every 24 seconds, 54 seconds, and 56 seconds. If they coincide at 10:20:00, when will they next coincide?

The numbers (in millions) of coconut, guava, mango and apple trees in a region in 2010 and 2020 are shown in the following figure — coconut 15 → 12, guava 25 → 22, mango 20 → 18, apple 30 → 35. The maximum relative change in numbers was for

Some, but not all, faces of a six-faced cubical fair die are painted red (R) and the remaining green (G); and the die is thrown until red faces come up on top 4 times. Consider the following sequences of colours listed left to right as they appear on the top. A: GRRRR. B: GRGRRR. Which one of the following is true?

From a fully-filled vessel of 12-litre capacity, to bring 6 litres of water into an empty vessel of 8-litre capacity, what is the minimum number of times water must be poured, given that an empty 5-litre vessel is also available for use?

A lady bought some apples, each costing Rs. 25, and some bananas each costing Rs. 6, for a total of Rs. 378. In how many ways could she have chosen the numbers of apples and bananas?

Suppose $a_1,a_2,\dots ,a_{300}$ are integers such that $a_i$₋${}_1+a_i+a_i$₊${}_1=2025$ for all i = 2, 3, …, 299. If $a_7=-5,a_9=37$, then the value of $a_{106}$ is

How many 5-digit numbers can be formed from the digits 0, 2, 3, 4, 6, 7 and 9, using each at most once, which are divisible by 5?

A recent survey suggests that the total fertility rate in a country has fallen below 2.1, the population replacement ratio. This necessarily implies that the

In a class, 40% and 20% students passed in Mathematics and Physics, respectively, and 10% students passed in both subjects. What is the probability of a randomly selected student to have passed in Physics if the student already passed in Mathematics?

The value of $1+(1/2^1+1/3)+(1/2^2+1/5+1/6+1/7)+\cdots +(1/2^9+\cdots +1/1023)$ lies between

In a community, some artists are teachers, no teacher is a painter, all painters are artists, and all teachers are professionals. Then it can be definitely asserted that