# Class 9th | Chapter 12 Herons formula | Practices paper - 1

Red Star(*) is a Correct Answer

Section A consists of 12 questions of 1 mark each

#### 1. The area of an equilateral triangle with side 4√3 cm is :(√3 = 1.732 )

- 20 cm2
- 20√3 cm2
- 18.784 cm2
- 20.784 cm2*

#### 2.The area of ∆ABC in which AB = BC = 4 cm and ∠B=90^o is :

- 16 cm2
- 8 cm2*
- 4 cm2
- 12 cm2

#### 3.The perimeter of an equilateral triangle is 60m. its area is :

- 10√3 m2
- 100√3 m2*
- 15√3 m2
- 20√3 m2

#### 4.The edge of a triangular board are 6 cm , 8 cm , 10 cm. the cost of painting it at rate of 9 paise per cm2 is :

- Rs 2
- Rs 3
- Rs 2.16*
- Rs 2.48

#### 5.The Side of a triangle are 7 cm , 24 cm and 25 cm. its area is :

- 168 cm2
- 84 cm2*
- 87.5 cm2
- 300 cm2

#### 6.The base of a right triangle is 8cm and hypotenuse is 10cm , its area will be :

- 24 sq cm *
- 40 sq cm
- 48 sq cm
- 80 sq cm

#### 7.The sides of a triangle are 35 cm , 54 cm and 61 cm, respectively . the length of its longest altitude

- 16√5 cm
- 10√5 cm
- 24√5 cm *
- 28 cm

#### 8.Area of an equilateral triangle , of each side 2a units is

- √3/4 a^2 sq.unit
- √3/2 a^2 sq.unit
- √3 a^2 sq.unit *
- 2√3 a^2 sq.unit

#### 9.The length of each side of an equilateral triangle having an area of 9√3 cm2 is

- 8 cm
- 36 cm
- 4 cm
- 6 cm *

#### 10.The sides of a triangle are in the ratio of 3 : 4 : 5 if perimeter is 36 cm , then what is its area ?

- 32 cm2
- 67 cm2
- 54 cm2*
- 72 cm2

#### 11.Area of an isosceles right triangle is 8 cm2 .its hypotenuse

- √32 cm*
- 4 cm
- 4√3 cm
- 2√6 cm

#### 12.If s - a = 90 , s - b =50 , s – c = 10 what value of a ;

- 50
- 60*
- 70
- 30

Section B consists of 4 questions of 2 mark each

- Find the perimeter of an isosceles right triangle having an area of 100 cm^2
- Side of a triangle are 70cm, 80 cm and 90 cm . find its area
- The area of a triangle is 48 cm^2. Its base 12 cm. find its corresponding altitude
- The base of an isosceles triangle is 4 cm and its perimeter is 20cm . find its area

Section C consists of 1 Case Study of 5 mark each

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