2023 Maths Olympiad (NCERT) Question Paper

Let x be any rational number, then x + 0 is equal to

• x

• 0

• -x

• Not defined

Answer explanation

For any rational number x, adding 0 does not change its value. Therefore, x + 0 equals x, making the correct answer x.

Which of the following is not a random experiment?

• Tossing a coin

• Rolling a dice

• Choosing a card from a deck of 52 cards

• Throwing a stone from a roof of a building

Answer explanation

Throwing a stone from a roof is deterministic; the outcome is predictable and not subject to chance. In contrast, tossing a coin, rolling a dice, and choosing a card involve randomness.

The shifting of a number from one side of an equation to other is called

• Transposition

• Ditributivity

• Commutativity

• Associativity

Answer explanation

The shifting of a number from one side of an equation to the other is known as transposition. This process involves rearranging the equation while maintaining its equality, making 'transposition' the correct choice.

43/34 - y = - then y=

• 2

• 2/3

• 4

• 2/4

Answer explanation

To solve for y, rearrange the equation: y = 43/34. Simplifying 43/34 gives 1.26, which is equivalent to 2/3 when expressed as a fraction. Thus, the correct answer is 2/3.

If three angles of a quadrilateral are each equal to 75, the fourth angle is

• 150

• 135

• 45

• 75

Answer explanation

The sum of angles in a quadrilateral is 360 degrees. If three angles are 75 degrees each, their total is 225 degrees. Therefore, the fourth angle is 360 - 225 = 135 degrees.

For which of the following, diagonals bisect each other?

• Square

• Quadrilateral

• Trapezium

• Kite

Answer explanation

In a square, all sides are equal and angles are right angles, which ensures that the diagonals bisect each other at right angles and are equal in length. Other shapes like quadrilaterals, trapeziums, and kites do not guarantee this property.

Which of the following is a regular polyhedron?

• cube

• cuboid

• Triangular Prism

• Square Prism

Answer explanation

A regular polyhedron has identical faces that are regular polygons. The cube fits this definition, as it has six square faces. In contrast, a cuboid has rectangular faces, and prisms have different polygonal bases, making them irregular.

Which of the following is a two Dimensional figure?

• Square Prism

• Rectangular Prism

• Square Pyramid

• Rectangle

Answer explanation

A rectangle is a two-dimensional figure defined by its length and width. In contrast, a square prism, rectangular prism, and square pyramid are three-dimensional shapes, which have volume and depth.

The usual form of 1000a + 10b + c is

• abc

• abco

• aobc

• aboc

Answer explanation

The expression 1000a + 10b + c represents a three-digit number where 'a' is the hundreds place, 'b' is the tens place, and 'c' is the units place. Thus, it is correctly represented as 'abc'.

Every point on the x axis is of the form

• (0, y)

• (x, 0)

• (x, y)

• (x, 1)

Answer explanation

Every point on the x-axis has a y-coordinate of 0, which means they are of the form (x, 0). Therefore, the correct choice is (x, 0), as it accurately represents all points along the x-axis.