CAT Previous Year Questions | Polygon

· by IIMking

Let’s Crack CAT 2026

Log in to track · your CAT progress
  1. CAT 2022 QA Slot 1 | Geometry - Quadrilaterals & Polygons CAT Question
    A trapezium ABCD has side AD parallel to BC. ∠BAD = 90°, BC = 3 cm and AD = 8 cm. If the perimeter of this trapezium is 36 cm, then its area, in sq cm, is
EXPLANATION

 

  1. CAT 2022 QA Slot 2 | Geometry - Quadrilaterals & Polygons CAT Question
    Regular polygons A and B have number of sides in the ratio 1 : 2 and interior angles in the ratio 3 : 4. Then the number of sides of B equals
EXPLANATION

Correct Answer: 10

Let the number of sides of polygons A and B be n and 2n, respectively

The number of sides of polygon B is 2*5, i.e. 10

  1. CAT 2022 QA Slot 3 | Geometry - Quadrilaterals & Polygons CAT Question
    The lengths of all four sides of a quadrilateral are integer valued. If three of its sides are of length 1 cm, 2 cm and 4 cm, then the total number o possible lengths of the fourth side is

(a) 5

(b) 4

(c) 3

(d) 6

EXPLANATION

The correct answer is A:5
To determine the possible lengths of the fourth side of the quadrilateral,we need to consider the triangle inequality theorem.According to this theorem, the sum of the lengths of any two sides of a triangle must be greater than the length of the third side.This principle also holds for quadrilaterals. 
Given the lengths of the three sides as 1cm, 2cm, and 4cm, we can consider all the possible combinations of these sides as two sides of the quadrilateral.Let's check each case: 
1cm+2cm> 4cm (True) 
1cm+4cm> 2cm (True) 
2cm+4cm> 1 cm (True) 
Since all three combinations satisfy the triangle inequality theorem,any of them can form a valid triangle,and consequently,a quadrilateral with the given side lengths. 
Now,let's consider the possible lengths of the fourth side for each combination: 
For 1cm+2cm> 4cm: 
The fourth side can have a length between |1cm-2cm|+1 and 1cm+2cm-1. 
This gives us a range of possible lengths: 1 to 2cm. 
For 1cm+4cm> 2cm: 
The fourth side can have a length between |1cm - 4cm|+1 and 1cm+ 4cm- 1. 
This gives us a range of possible lengths: 2 to 4cm. 
For 2cm+ 4cm> 1cm: 
The fourth side can have a length between |2cm- 4cm|+ 1 and 2cm+ 4cm- 1. 
This gives us a range of possible lengths: 3 to 5cm. 
Now,let's combine the ranges from all three cases: 1-2cm,2-4cm, and 3-5cm. 
The possible integer lengths for the fourth side are: 1, 2, 3, 4, 5. 
Therefore, the total number of possible lengths for the fourth side is 5. 

  1. CAT 2021 QA Slot 1 | Geometry - Quadrilaterals & Polygons CAT Question
    Suppose the length of each side of a regular hexagon ABCDEF is 2 cm. If T is the mid point of CD, then the length of AT, in cm, is

(a) √14

(b) √12

(c) √13

(d) √15

EXPLANATION

T is the midpoint of CD in the given regular hexagon ABCDEF

CT=DT=2/2=1

Draw AT, AD and AC

By the property of hexagon,

AD=2×BC=2×2=4=2×=2×2=4

∠ABC=∠BCD=120∘∠=∠=120∘

We have, AB=BC=CD=2

∠ACD=120∘−30∘=90∘∠=120∘−30∘=90∘

ACD is a right triangle and AT is its median

AC2=AD2−CD2= 42 - 22 = 12

Using Apollonius's theorem,

AC2+AD2=2(AT2+DT2)

12 + 42 = 2(AT2+12)

AT = √13

Ans: ≈3.605551 cm

  1. CAT 2021 QA Slot 2 | Geometry - Quadrilaterals & Polygons CAT Question
    The sides AB and CD of a trapezium ABCD are parallel, with AB being the smaller side. P is the midpoint of CD and ABPD is a parallelogram. If th difference between the areas of the parallelogram ABPD and the triangle BPC is 10 sq cm, then the area, in sq cm, of the trapezium ABCD is

(a) 20

(b) 30

(c) 40

(d) 25

EXPLANATION

It is given that: 
DP =x 
∴ AB =x
Now DP=CP So CD = 2x

Now, if we denote the height of the trapezium as 'h,' 
we can express the area of parallelogram ABPD as 'xh'

Now, based on the given condition

  1. CAT 2021 QA Slot 2 | Geometry - Quadrilaterals & Polygons CAT Question
    If a rhombus has area 12 sq cm and side length 5 cm, then the length, in cm, of its longer diagonal is

(a) √13 + √12

(b) √37 + √13

(c) (√13 + √12)/2

(d) (√37 + √13)/2

EXPLANATION

Answer: A
All the sides of the rhombus are equal.
The area of a rhombus is 12 cm2.
Considering d1 to be the length of the longer diagonal, d2 to be the length of the shorter diagonal.

The area of a rhombus is

d1*d2 = 24.

  1. CAT 2021 QA Slot 3 | Geometry - Quadrilaterals & Polygons CAT Question
    A park is shaped like a rhombus and has area 96 sq m. If 40 m of fencing is needed to enclose the park, the cost, in INR, of laying electric wires alon its two diagonals, at the rate of ₹125 per m, is
EXPLANATION
  1. CAT 2021 QA Slot 3 | Geometry - Quadrilaterals & Polygons CAT Question
    Let ABCD be a parallelogram. The lengths of the side AD and the diagonal AC are 10 cm and 20 cm, respectively. If the angle ∠ADC is equal to 30° the the area of the parallelogram is sq. cm. is

(a) 25(√3 + √15)/2

(b) 25(√5 + √15)

(c) 25(√3 + √15)

(d) 25(√5 + √15)/2

EXPLANATION
  1. CAT 2020 QA Slot 1 | Geometry - Quadrilaterals & Polygons CAT Question
    A circle is inscribed in a rhombus with diagonals 12 cm and 16 cm. The ratio of the area of circle to the area of rhombus is

(a) 5π/18

(b) 2π/15

(c) 3π/25

(d) 6π/25

EXPLANATION

  1. CAT 2020 QA Slot 2 | Geometry - Quadrilaterals & Polygons CAT Question
    The sum of the perimeters of an equilateral triangle and a rectangle is 90 cm. The area, T, of the triangle and the area, R, of the rectangle, both in s cm, satisfy the relationship R = T². If the sides of the rectangle are in the ratio 1 : 3, then the length, in cm, of the longer side of the rectangle, is

(a) 27

(b) 24

(c) 18

(d) 21

EXPLANATION

Let the sides of the rectangle be "a" and "3a" m.

Hence the perimeter of the rectangle is 8a. Let the side of the equilateral triangle be "m" cm.

Hence the perimeter of the equilateral triangle is "3m" cm. Now we know that 8a+3m=90......(1)

Hence a=9 and the longer side of the rectangle will be 3a=27cm

  1. CAT 2020 QA Slot 3 | Geometry - Quadrilaterals & Polygons CAT Question
    In a trapezium ABCD, AB is parallel to DC, BC is perpendicular to DC and ∠BAD = 45°. If DC = 5 cm, BC = 4 cm, the area of the trapezium in sq.cm is
EXPLANATION

Given, BC = DE = 4

CD = BE = 5

12.CAT 2019 QA Slot 2 | Geometry - Quadrilaterals & Polygons CAT Question
Let A and B be two regular polygons having a and b sides, respectively. If b = 2a and each interior angle of B is 3/2 times each interior angle of A, the each interior angle, in degrees, of a regular polygon with a + b sides is

EXPLANATION
  1. CAT 2018 QA Slot 1 | Geometry - Quadrilaterals & Polygons CAT Question
    Points E, F, G, H lie on the sides AB, BC, CD, and DA, respectively, of a square ABCD. If EFGH is also a square whose area is 62.5% of that of ABCD an CG is longer than EB, then the ratio of length of EB to that of CG is

(a) 2 : 5

(b) 4 : 9

(c) 3 : 8

(d) 1 : 3

EXPLANATION

It is given that EFGH is also a square whose area is 62.5% of that of ABCD. Let us assume that E divides AB in x : 1. Because of symmetry we can se that points F, G and H divide BC, CD and DA in x : 1. Because of symmetry we can se that points F, G and H divide BC, CD and DA in x : 1.

Let us assume that 'x+1' is the length of side of square ABCD. 

  1. CAT 2018 QA Slot 1 | Geometry - Quadrilaterals & Polygons CAT Question
    In a parallelogram ABCD of area 72 sq cm, the sides CD and AD have lengths 9 cm and 16 cm, respectively. Let P be a point on CD such that AP i perpendicular to CD. Then the area, in sq cm, of triangle APD is

(a) 12√3

(b) 24√3

(c) 18√3

(d) 32√3

EXPLANATION

Area of the parallelogram ABCD = (base) (height)

= CD × AP = 72 sq.cm.

⇒ 72 = 9 × (AP) ⇒ AP = 8cm

  1. CAT 2018 QA Slot 1 | Geometry - Quadrilaterals & Polygons CAT Question
    Let ABCD be a rectangle inscribed in a circle of radius 13 cm. Which one of the following pairs can represent, in cm, the possible length and breadth o ABCD?

(a) 24, 12

(b) 24, 10

(c) 25, 10

(d) 25, 9

EXPLANATION

We know that AC is the diameter and ABC = 90°. AC = 2*13 = 26 cm.

In right angle triangle ABC,

Let us check with the options. Therefore, we can say that option A is the correct answer.

Therefore, we can say that option A is the correct answer.

  1. CAT 2018 QA Slot 2 | Geometry - Quadrilaterals & Polygons CAT Question
    A parallelogram ABCD has area 48 sqcm. If the length of CD is 8 cm and that of AD is s cm, then which one of the following is necessarily true?

(a) s ≠ 6

(b) s ≥ 6

(c) 5 ≤ s ≤ 7

(d) s ≤ 6

EXPLANATION

Answer:

As,sin0 < 1

Step-by-step explanation:

Area of parellogram ABCD= 2*Area of triangle ACD

48= 2* area of triangle ACD

Area of triangle of ACD =24 because 48/2=24

(1/2) * CD * DA * SinADC =24

=(1/2) *8* DA *SinADC =24

Ad *SinADC =6

ANSWER

As,sin0 < 1

  1. CAT 2018 QA Slot 2 | Geometry - Quadrilaterals & Polygons CAT Question
    The area of a rectangle and the square of its perimeter are in the ratio 1 ∶ 25. Then the lengths of the shorter and longer sides of the rectangle are i the ratio ?

(a) 1 : 3

(b) 2 : 9

(c) 1 : 4

(d) 3 : 8

EXPLANATION

Let 'a' and 'b' be the length of sides of the rectangle, (a > b)

Area of the rectangle = a*b

Perimeter of the rectangle = 2*(a+b)

=>a*b/(2*(a + b))2 = 1/25

=> 25ab = 4(a + b)2

=> 4a2 - 17ab + 4b2 = 0

=> (4a - b)(a - 4b) = 0

=> a = 4b or b/4

We initially assumed that a > b, therefore a ≠ 4. Hence, a = 4b => b: a = 1: 4

  1. CAT 2017 QA Slot 2 | Geometry - Quadrilaterals & Polygons CAT Question
    Let ABCDEF be a regular hexagon with each side of length 1 cm. The area (in sq cm) of a square with AC as one side is

(a) 3√2

(b) 3

(c) 4

(d) √3

EXPLANATION

AC is base of an isoceles triangle ABC where AB and BC are side lengths of a regular hexagon. Interior angles of hexagon are 120∘ each, therefore base angles are 30∘ each.

By cosine rule,

  1. CAT 2017 QA Slot 2 | Geometry - Quadrilaterals & Polygons CAT Question
    ABCD is a quadrilateral inscribed in a circle with centre O. If ∠COD = 120 degrees and ∠BAC = 30 degrees, then the value of ∠BCD (in degrees) is
EXPLANATION

Following the conditions of question, we get the figure as:

∠COD = 1200 (Given)
Then, ∠DAC = 600 (Half of ∠COD i.e. 1200)
Therefore, ∠BAD = 300+600=900
Hence, ∠BCD = 1800 - ∠BAD (Opposite angles of a cyclic quadrilateral are supplementary angles).
∠BCD = 1800–900=900

    Question 1 of 31

    Q1CAT 2008
    Figure for this questionFigure for this question

    Consider a square ABCD with midpoints E, F, G, H of AB, BC, CD and DA respectively. Let L denote the line passing through F and H. Consider points and Q, on L and inside ABCD, such that the angles APD and BQC both equal 120°. What is the ratio of the area of ABQCDP to the remaining area insid ABCD?

    0/31 tried · 0 right

    What next

    Admit cards · CAT admit card · © Cetking Universe · Terms & Privacy · By using this site, you agree to Cetking's Terms.