SSC CGL Undated PYQs

Question 1

Which of the following causes fly ash? ?

Accepted Answer

Fly ash is a fine powder produced as a byproduct of burning pulverized coal in electric generation power plants. Therefore, coal combustion power plants are the primary source.

Question 2

Which of the following is an ore of Aluminium?

Accepted Answer

Cryolite (Na3AlF6) is an important ore of aluminium, used in its electrolytic extraction. Galena is an ore of lead, and cinnabar is an ore of mercury.

Question 3

If a(a + b + c) = 45, b(a + b + c) = 75 and c(a + b + c) = 105, then what is the value of (a2 + b2 + c2)?

Accepted Answer

Add the three equations: (a+b+c)^2 = 45+75+105 = 225, so a+b+c = 15. Then a=3, b=5, c=7. Thus, a^2+b^2+c^2 = 9+25+49 = 83.

Question 4

Ozone is an ______ of oxygen.

Accepted Answer

Ozone (O3) and dioxygen (O2) are allotropes of oxygen because they are different structural forms of the same element existing in the same physical state.

Question 5

How much water (in litres) must be added to 80 litres solution of milk and water containing 10% milk, so that it becomes a 5% milk solution?

Accepted Answer

Initial milk is 10% of 80L = 8L. To make this 8L equal to 5% of the new mixture, the total volume must be 160L. Thus, 160 - 80 = 80L of water must be added.

Question 6

The SI unit of acceleration is _______________.

Accepted Answer

Acceleration is the rate of change of velocity. Since velocity is measured in m/s and time in seconds, acceleration is (m/s)/s, which equals meters per second squared.

Question 7

If 4 * 5 % 3 = 8000 and 2 * 3 % 2 = 36, then 4 * 3 % 3 = ?

Accepted Answer

The pattern is (a * b)^c. For 4 * 5 % 3, (4*5)^3 = 20^3 = 8000. Applying this to 4 * 3 % 3 gives (4*3)^3 = 12^3 = 1728.

Question 8

In Indian constitution, the method of election of President has been taken from which country?

Accepted Answer

The method of election of the President, Directive Principles of State Policy (DPSP), and nomination of members to Rajya Sabha are borrowed from the Irish Constitution.

Question 9

If cos2 θ – sin θ = ¼, then what is the value of sin θ?

Accepted Answer

Substitute cos² θ = 1 - sin² θ. The equation becomes 1 - sin² θ - sin θ = 1/4, which simplifies to 4sin² θ + 4sin θ - 3 = 0. Solving gives sin θ = 1/2.

Question 10

The coil wire in the electric room heater or electric cooking heater is called __________.

Accepted Answer

The heating coil in appliances like room heaters and geysers is called a heating element. It converts electrical energy into heat due to its high resistance.

Question 11

A healthy adult man has, on an average, ________ (in millions) of RBCs mm-3 of blood.

Accepted Answer

A healthy adult male typically has an RBC count ranging from 5 to 5.5 million per cubic millimeter of blood. This is essential for adequate oxygen transport throughout the body.

Question 12

Takshashila University was located between which two rivers?

Accepted Answer

Takshashila (Taxila) was a renowned ancient university located in the northwestern region of the Indian subcontinent, situated precisely between the Indus and Jhelum rivers in present-day Pakistan.

Question 13

An economic system combining private and state enterprise is called as _____

Accepted Answer

A mixed economy incorporates elements of both capitalism (private enterprise) and socialism (state/government control) to balance economic freedom with social welfare.

Question 14

Why does Western Ghats and Eastern Ghats both receive suﬀicient rainfall but Deccan Plateau receives scanty rainfall?

Accepted Answer

The Deccan Plateau lies on the leeward side of the Western Ghats. Moisture-laden winds drop their rain on the windward side, leaving the plateau dry as a rain shadow area.

Question 15

ABCD is an isosceles trapezium such that AD||BC, AB = 5 cm, AD = 8 cm and BC = 14 cm. What is the area (in cm2) of trapezium?

Accepted Answer

Base difference is 14 - 8 = 6. Since it's isosceles, the base of the right triangle is 3. Height = √(5² - 3²) = 4 cm. Area = 1/2 × (8 + 14) × 4 = 44 cm².

Question 16

In a triangle PQR, ∠Q = 90°. If PQ = 12 cm and QR = 5 cm, then what is the radius (in cm) of the circumcircle of the triangle?

Accepted Answer

In a right-angled triangle, the circumradius is half the hypotenuse. Hypotenuse PR = √(12² + 5²) = 13 cm. So, the circumradius is 13 / 2 = 6.5 cm.

Question 17

The 3rd and 9th term of an arithmetic progression are -8 and 10 respectively. What is the 16th term?

Accepted Answer

Using the AP formula: a+2d = -8 and a+8d = 10. Solving these gives d=3 and a=-14. The 16th term is a+15d = -14 + 45 = 31.

Question 18

Who among the following was NOT one of the recipients of Major Dhyan Chand Lifetime Achievement Award for the year 2016?

Accepted Answer

In 2016, the Major Dhyan Chand Lifetime Achievement Award was given to Rajendra Pralhad Shelke (Rowing), Sylvanus Dung Dung (Hockey), and Sathi Geetha (Athletics). Amit Kumar was not a recipient.

Question 19

Advik's birthday is on Monday 19th June. On what day of the week will be Nishith's Birthday in the same year if Nishith was born on 17th November?

Accepted Answer

Days from June 19 to Nov 17: 11(Jun) + 31(Jul) + 31(Aug) + 30(Sep) + 31(Oct) + 17(Nov) = 151 days. 151 ÷ 7 leaves a remainder of 4. Monday + 4 days = Friday.

Question 20

The tangents drawn at points A and B of a circle with centre O, meet at P. If ∠AOB = 120° and AP = 6 cm, then what is the area of triangle (in cm2) APB?

Accepted Answer

Since tangents AP and BP are equal and ∠APB = 180° - 120° = 60°, triangle APB is equilateral. With side 6 cm, its area is (√3/4) × 6² = 9√3 cm².