Geometry Questions

Multiple choice general knowledge math & puzzles
  1. 11/14

  2. 22/27

  3. 13/27

  4. 13/14

Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

For a square of side 6cm, the inscribed circle has diameter 6cm (radius 3cm). Circle area = πr² = 9π. Square area = 6² = 36. The ratio is 9π/36 = π/4 ≈ 0.785. Among options, 11/14 ≈ 0.786 is the closest approximation to π/4.

Multiple choice general knowledge math & puzzles
  1. 16

  2. 32

  3. 48

  4. 64

  5. 8

  6. none

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The largest square inscribed in a circle has a diagonal equal to the circle's diameter, which is 8 cm. The area of a square with diagonal $d$ is $d^2 / 2$. Thus, the area is $8^2 / 2 = 64 / 2 = 32$ square centimeters. Distractors represent incorrect formulas or area of the circumscribed square (64).

Multiple choice
  1. πa2Cot2(θ/2)

  2. 2πa2(1+Cot2(θ/2))

  3. πa2(1+Cot2(θ/2))

  4. 4πa2(1+Cot2(θ/2))

  5. (πa2/4)(1+Cot2(θ/2))

Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

According to the question, a chord of length 2a makes an angle θ at the centre. So, in the triangle, side opposite to angle θ is 2a. r (r = radius of the circle) In that triangle, applying the Cosine Law, Cos θ = (r2 + r2 - (2a)2)/(2r2) Cos θ = (2r2 - 4a2)/(2r2) Solving, we get r2 = (2a2)/(1-Cosθ)------------(1) Now, Cos θ can be written as Cos 2(θ/2) (Cos 2x = (1 - tan2x)/(1 + tan2x)) Cos 2(θ/2) = (1 - tan2(θ/2))/(1 + tan2(θ/2)) Cos θ = (1 - tan2(θ/2))/(1 + tan2(θ/2)) 1 - Cos θ = 2tan2(θ/2)/(1 + tan2(θ/2)) It can be written as:1 - Cos θ = 2/(1 + Cot2(θ/2)) Divinding numerator and denominator by tan2(θ/2) and substituting the value of 1 - Cos θ in (1), we get r2 = a2(1 + Cot2(θ/2)) Now, area of circle is πr2. So, area = πa2(1+Cot2(θ/2)) (Correct Answer)

Multiple choice
  1. 4 cm

  2. 1 cm

  3. 2 cm

  4. 0.5 cm

Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Area of right $\triangle$ABC = 1/2 x AB x BC= 1/2 x (6 x 8)cm2 = 24 cm2     AC2 = AB2 + BC2                             64 cm2 + 36 cm2 = 100 cm2. AC = 10 cm.  Also, area ($\triangle$ABC) = ar ($\triangle$OBC) + ar ($\triangle$OCA) + ar ($\triangle$OAB)= 1/2 (BC x r) + 1/2 (AC x r) + 1/2 (AB x r)= 1/2 r (6 + 10 +8) cm = 12 r cm 12 r cm = 24 cm2 $\Rightarrow$ r = 2 cm

Multiple choice maths area of complex plane figures 2d and 3d figures

Find the area of equilateral  triangle inscribed in a circle of unit radius.

  1. 3/4

  2. $\dfrac {3\sqrt { 3 } }{4}$
  3. 3

  4. $\frac { 3\sqrt { 3 } }{ 2 } $
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The radius of circumcircle  of equilateral triangle is  $\dfrac 23h=1\h=\dfrac 32$

The side of equilateral triangle is given as $\dfrac{4h}{\sqrt 3} \\dfrac{4}{\sqrt 3}\times \dfrac 32=2\sqrt 3$ 
The area of triangle is given as $\dfrac {\sqrt 3}{4}(2\sqrt 3)^2=3\sqrt 3$

Multiple choice maths area of complex plane figures 2d and 3d figures

A square is inscribed in a circle of radius $7: cm$. Find area of the square.

  1. $98 \: cm^{2}$
  2. $97 \: cm^{2}$
  3. $91 \: cm^{2}$
  4. $90 \: cm^{2}$
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Given,
Radius of the circle $=7:cm$
Let the side of the square be $a:cm$.
A square when inscribed in a circle then the diameter of the circle must be diagonal of the square.
Therefore,
Diagonal of square $=\sqrt {a^2+a^2}$
                                 $=a\sqrt 2$
Now,
Diameter of the circle $=2\times 7$
                                  $=14:cm$
$=>\sqrt 2 a=14$
$=>a=\dfrac{14}{\sqrt 2}$
$=>a=7\sqrt 2: cm$
Therefore,
Area of square $=a^2$
                       $=(7\sqrt 2 cm)^2$
                       $=(7\sqrt 2 cm)(7\sqrt 2 cm)$
                       $=98: cm^2$

Multiple choice maths area of complex plane figures 2d and 3d figures

If one side of a square is 2.4 m. Then what will be the area of the circle inscribed in the square?

  1. $1.44 \displaystyle\, m^{2} $
  2. $\displaystyle 1\frac{11}{25}\pi $ $\displaystyle m^{2} $
  3. $\displaystyle \frac{11}{25}\pi $ $\displaystyle m^{2} $
  4. None of these

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The radius of the circle inscribed in the square
of side 2.4m
$\displaystyle r=\dfrac{2.4}{4}m=1.2m$
$\displaystyle \therefore$ Area of the circle $\displaystyle =\pi r^{2}$ square units
$\displaystyle =\pi \times 1.2 m\times 1.2 m$
$\displaystyle =1.44 \pi m^{2}$

$\displaystyle =1\dfrac{11}{25}\pi m^{2}$
$\displaystyle \therefore $ The required area $\displaystyle =1\frac{11}{25}\pi m^{2}$

Multiple choice intersection of a line and a parabola conic section maths

If a$\ne $b then the length of common chord of the circles ${\left( {x - a} \right)^2} + {\left( {y - b} \right)^2} = {c^2}$ and ${\left( {x - {b^{}}} \right)^2} + {\left( {y - a} \right)^2} = c^2$ is 

  1. $\sqrt {{c^2} - {{\left( {a - b} \right)}^2}} $
  2. $\sqrt {4{c^2} - 2{{\left( {a - b} \right)}^2}} $
  3. $\sqrt {3{c^2} - {{\left( {a - b} \right)}^2}} $
  4. $\sqrt {2{c^2} - {{\left( {a - b} \right)}^2}} $
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

We have,

${{\left( x-a \right)}^{2}}+{{\left( y-b \right)}^{2}}={{c}^{2}}$ 
${{S} _{1}}\equiv {{x}^{2}}+{{a}^{2}}-2ax+{{y}^{2}}+{{b}^{2}}-2by-{{c}^{2}}=0$               …….. (1)

 

${{\left( x-b \right)}^{2}}+{{\left( y-a \right)}^{2}}={{c}^{2}}$

${{S} _{2}}\equiv {{x}^{2}}+{{b}^{2}}-2bx+{{y}^{2}}+{{a}^{2}}-2ay-{{c}^{2}}=0$                        ……… (2)

 

Since, $a\ne b$

 

Centre of the circle ${{S} _{1}}=\left( a,b \right)$ and radius ${{r} _{1}}=c$.

 

We know that the equation of common chord is ${{S} _{1}}-{{S} _{2}}=0$

 

So, the equation is

$\left( b-a \right)x+\left( a-b \right)y=0$             …….. (3)

 

We know that the length of common chord is

$=2\sqrt{{{r} _{1}}^{2}-{{d} _{1}}^{2}}$                      ………. (4)

Where ${{r} _{1}}=$ radius and ${{d} _{1}}$ is the length of perpendicular drawn from the centre to the chord.

 

So,

${{d} _{1}}=\left| \dfrac{\left( b-a \right)a+\left( a-b \right)b}{\sqrt{{{\left( b-a \right)}^{2}}+{{\left( a-b \right)}^{2}}}} \right|$

$ {{d} _{1}}=\left| \dfrac{ab-{{a}^{2}}+ab-{{b}^{2}}}{\sqrt{{{\left( a-b \right)}^{2}}+{{\left( a-b \right)}^{2}}}} \right| $

$ {{d} _{1}}=\left| \dfrac{2ab-{{a}^{2}}-{{b}^{2}}}{\sqrt{2{{\left( a-b \right)}^{2}}}} \right| $

$ {{d} _{1}}=\left| \dfrac{-{{\left( a-b \right)}^{2}}}{\sqrt{2{{\left( a-b \right)}^{2}}}} \right| $

$ {{d} _{1}}=\left| \dfrac{-\left( a-b \right)}{\sqrt{2}} \right| $

$ {{d} _{1}}=\dfrac{\left( a-b \right)}{\sqrt{2}} $

 

From equation (4),

The length of common chord $ =2\sqrt{{{c}^{2}}-{{\left( \dfrac{a-b}{\sqrt{2}} \right)}^{2}}} $

$ =2\sqrt{{{c}^{2}}-{{\dfrac{\left( a-b \right)}{2}}^{2}}} $

$ =2\sqrt{{{\dfrac{2{{c}^{2}}-\left( a-b \right)}{2}}^{2}}} $

$ =\sqrt{{{\dfrac{8{{c}^{2}}-4\left( a-b \right)}{2}}^{2}}} $

$ =\sqrt{4{{c}^{2}}-2{{\left( a-b \right)}^{2}}} $

 

Hence, this is the answer.

Multiple choice maths construction circumscribing and inscribing a circle on a regular hexagon constructions related to a circle construction of polygons construction of tangent to a circle construction of tangents construction of line segment and circle of given radius construction related to lines

How many equal parts you will cut the circle to draw inscribing hexagon?

  1. $4$
  2. $5$
  3. $6$
  4. $7$
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Hexagon is a $6$-sided polygon.
So we will cut the circle into $6$ equal parts.

Multiple choice maths construction circumscribing and inscribing a circle on a regular hexagon constructions related to a circle construction of polygons construction of tangent to a circle construction of tangents construction of line segment and circle of given radius construction related to lines

When constructing the circles circumscribing and inscribing a regular hexagon with radius $3$ m, then inscribing hexagon length of each side is

  1. $1m$
  2. $2m$
  3. $3m$
  4. $4m$
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

When constructing the circles circumscribing and inscribing a regular hexagon with radius $3$ m, then inscribing hexagon length of each side is $3$ m.

Multiple choice maths how many squares area of rectangular paths comparing areas spaces and boundaries - 2

Find the area of a square inscribed in a circle of radius $\displaystyle 5\sqrt{2}$ cm (in $\displaystyle cm^{2}$)

  1. 75

  2. 100

  3. 125

  4. 150

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The diagonal of the square will be equal to the diameter of the circle.
So,diagonal of the square $ = 2 \times 5 \sqrt {2} = 10 \sqrt {2} $

Diagonal of a square $ = \sqrt {2} \times side $
So, $ 10 \sqrt {2} = \sqrt {2} \times side $
$ => Side  =  10  cm $

Area of the square $ = { side }^{ 2 } = { 10 }^{ 2 } = 100 $ sq cm