SSC CGL Undated PYQs

Question 1

The closest example of a centrally planned economy is the __________ for the major part of the 20th Century.

Accepted Answer

The Soviet Union operated a centrally planned (command) economy where the government made all major decisions regarding production, pricing, and distribution, unlike capitalist or mixed economies.

Question 2

A person lent Rs 10000 to B for 3 years and Rs 6000 to C for 4 years on simple interest at same rate of interest and received Rs 5400 in all from both of them as interest. What is the rate of interest (in %)?

Accepted Answer

Total simple interest is the sum of interest from B and C. (10000 × 3 × R)/100 + (6000 × 4 × R)/100 = 5400. This gives 300R + 240R = 5400, so 540R = 5400, meaning R = 10%.

Question 3

In the following question, select the related number from the given alternatives. 56 : 41 : : 94 : ?

Accepted Answer

The logic is (Product of digits) + (Sum of digits). For 56: (5×6) + (5+6) = 30 + 11 = 41. For 94: (9×4) + (9+4) = 36 + 13 = 49.

Question 4

If (x + y + z) = 12, xy + yz + zx = 44 and xyz = 48, then what is the value of x3 + y3 + z3?

Accepted Answer

Use the identity x³+y³+z³ - 3xyz = (x+y+z)[(x+y+z)² - 3(xy+yz+zx)]. Substituting the values gives x³+y³+z³ - 144 = 12[144 - 132] = 144. Thus, x³+y³+z³ = 288.

Question 5

Who discovered bacteria?

Accepted Answer

Antonie van Leeuwenhoek discovered bacteria in 1676 using a single-lens microscope of his own design. He originally called these microscopic organisms 'animalcules'.

Question 6

A __________ thread is actually stronger than a steel wire.

Accepted Answer

Nylon is a synthetic polymer known for its exceptional tensile strength and elasticity. A nylon thread of the same thickness can bear more weight than a steel wire.

Question 7

Animals like annelids and arthropods etc where the body can be divided into identical left and right halves in only one plane, exhibit ________ symmetry.

Accepted Answer

When an animal's body can be divided into identical left and right halves through a single central plane, it is called bilateral symmetry. Annelids and arthropods show this trait.

Question 8

Rohan borrowed a certain sum of money at simple interest. Rate of interest was 3% per annum for first 3 years, 4% per annum for next 5 years and 6% per annum for next 7 years. If he paid Rs 2059 as interest, then what is the sum borrowed (in Rs)?

Accepted Answer

Total simple interest is the sum of (rate × time) for each period: (3×3) + (4×5) + (6×7) = 71%. Since 71% of the principal equals Rs 2059, the principal is 2059 / 0.71 = Rs 2900.

Question 9

30% of a number exceeds 25% of the same number by 27. What is the value of the number?

Accepted Answer

The difference between 30% and 25% of the number is 5%. Since 5% equals 27, the total number (100%) is 27 multiplied by 20, which gives 540.

Question 10

The ratio of present ages of R and S is 11:17. Before 11 years the ratio of their ages was 11:20. What is R's present age (in years)?

Accepted Answer

Let present ages be 11x and 17x. (11x - 11) / (17x - 11) = 11/20. Solving gives 220x - 220 = 187x - 121, so 33x = 99, x = 3. R's age = 11(3) = 33.

Question 11

If sum of the areas of the circumcircle and the incircle of an equilateral triangle is 770 cm2, then what is the area (in cm2) of the triangle?

Accepted Answer

Let side be a. Circumcircle area = πa²/3, incircle area = πa²/12. Sum = 5πa²/12 = 770. Solving gives a² = 588. Triangle area = (√3/4)a² = 147√3.

Question 12

If A has got 20% more marks than B, then by what percent marks of B are less than the marks of A?

Accepted Answer

Let B's marks be 100, then A's marks are 120. The difference is 20. The percentage by which B is less than A is (20/120) × 100 = 16.66%.

Question 13

Δ DEF is right angled at E. If m ∠D = 30°. What is the length (in cm) of DE, if EF = 2√3 cm?

Accepted Answer

In right ΔDEF, tan(D) = EF / DE. So, tan(30°) = 2√3 / DE. Since tan(30°) = 1/√3, we get DE = 2√3 × √3 = 6 cm.

Question 14

On which principle does the hydraulic lift works? ?

Accepted Answer

Hydraulic lifts work on Pascal's law, which states that pressure applied to an enclosed fluid is transmitted equally and undiminished to every part of the fluid.

Question 15

In a certain code language, "who are you" is written as "432", "they is you" is written as "485" and "they are dangerous" is written as "295". How is "dangerous" written in that code language?

Accepted Answer

Comparing the sentences, 'you' = 4, 'are' = 2, and 'they' = 5. In 'they are dangerous' (295), removing 5 and 2 leaves 9 as the code for 'dangerous'.

Question 16

What is the simplified value of (cosec4 A – cot2 A) – (cot4 A + cosec2 A)?

Accepted Answer

Rearrange to (cosec^4 A - cot^4 A) - (cosec^2 A + cot^2 A). Using a^2 - b^2 and cosec^2 A - cot^2 A = 1, it simplifies to (cosec^2 A + cot^2 A) - (cosec^2 A + cot^2 A) = 0.

Question 17

In the following question, select the missing number from the given series. 21, 26, 33, 42, 53, ?

Accepted Answer

The differences between consecutive terms are consecutive odd numbers: +5, +7, +9, +11. The next difference is +13. So, 53 + 13 = 66.

Question 18

A chord of length 60 cm is at a distance of 16 cm from the centre of a circle. What is the radius (in cm) of the circle?

Accepted Answer

The perpendicular from the center bisects the chord. Half-chord = 30 cm. Using Pythagoras theorem, radius = √(30² + 16²) = √(900 + 256) = √1156 = 34 cm.

Question 19

Gurkiran's birthday is on Sunday 21st May. On what day of the week will be Shreyas's Birthday in the same year if Shreyas was born on 14th November?

Accepted Answer

Days from May 21 to Nov 14: May(10) + Jun(30) + Jul(31) + Aug(31) + Sep(30) + Oct(31) + Nov(14) = 177 days. 177 ÷ 7 leaves remainder 2. Sunday + 2 = Tuesday.

Question 20

What are the main components of Brass Alloy?

Accepted Answer

Brass is a widely used alloy primarily composed of copper and zinc. The proportion of zinc can be varied to create different types of brass with varying properties.