RBSE Solutions for Class 8 Maths Chapter 15 Surface Area and Volume In Text Exercise is part of RBSE Solutions for Class 8 Maths. Here we have given Rajasthan Board RBSE Class 8 Maths Chapter 15 Surface Area and Volume In Text Exercise.

Board |
RBSE |

Textbook |
SIERT, Rajasthan |

Class |
Class 8 |

Subject |
Maths |

Chapter |
Chapter 15 |

Chapter Name |
Surface Area and Volume |

Exercise |
In Text Exercise |

Number of Questions |
9 |

Category |
RBSE Solutions |

## Rajasthan Board RBSE Class 8 Maths Chapter 15 Surface Area and Volume In Text Exercise

**Page No: 180**

Question 1.

If a cuboid is formed by sticking three cubes of side x then what will be the dimensions of cuboid.

Solution:

Position I

Length = 3x

Breadth = x

Height = x

Position II

Length = x

Breadth = x

Height = 3x

**Page No: 181**

Question 2.

Find out surface area of a cube having side 3 cm. What will be the(RBSESolutions.com)surface area of 5 such cubes?

Solution:

Surface area of cube of side 3 cm.

= 6 a²

= 6(3)²

= 54 cm.²

Surface area of 5 cubes

= 54 x 5

= 270 cm.²

Question 3.

What will be the total surface area of 5 cubes having side 3 cm.? If they are stocked one after one, then how much surface area will be decreased?

Solution:

Total surface area of 5 cubes each of 3 side = 270 cm² (See the solution of question 1)

If 5 cubes are joined one(RBSESolutions.com)after one, then it becomes a cuboid whose length (l)

= 3 cm. + 3 cm. + 3 cm. + 3 cm. + 3 cm.

= 15 cm.

Breadth (b) = 3 cm.

Height (h) = 3 cm.

∴ Surface Area= 2 (lb + bh + hl).

= 2 (15 x 3 + 3 x 3 + 3 x 15)

= 2 (45 + 9 + 45)

= 198 cm²

∴ Hence, surface area will be reduced and the difference = 270 cm.² – 198 cm.²

= 72 cm.²

Question 4.

Find out lateral surface area of the given cuboid.

Solution:

Here, l = 10 cm.

b = 4 cm.

h = 4 cm.

∴Lateral surface area of cuboid

= 2 (l + b) h

= 2 (10 + 4) 4

= 112 cm.²

**Page No: 182**

Question 5.

Determine total surface area(RBSESolutions.com)of following cylinders

Solution:

(i) Here, r = \(\frac { 7 }{ 2 }\)

h = 10 cm

∴ Total surface are of cylinder

= 2πr (h + r)

**Page No: 186**

Question 6.

By arranging cubes of unit length And volume of cuboid so obtained

Solution:

**Page No: 187**

Question 7.

Find volume of cuboid(RBSESolutions.com)on basis of given measures –

Solution:

(i) Here, l = 8 cm.

b = 3 cm.

h = 2 cm.

∴ Volume of cuboid

= l x b x h

= 8 x 3 x 2

= 48 cm.³

(ii) Here, l = 1 cm.

b = 1 cm.

h = 7 cm.

∴ Volume of cuboid

= l x b x h

= 1 x 1 x 7

= 7 cm³

**Page No: 187**

Question 8.

Solution

**Page No: 188**

Question 9.

Determine volume(RBSESolutions.com)of the cube having side

(i) 1.5 cm

(ii) 4 m

Solution:

(i) 1.5 cm

Here, a = 1.5 cm

∴ Volume of cube = a³

= (1.5)³

= 1.5 x 1.5 x 1.5

= 3.375 cm³

(ii) 4 cm

Here, a = 4 cm

∴ Volume of cube = a³

= (4)³

= 4 x 4 x 4

= 64 cm³

We hope the given RBSE Solutions for Class 8 Maths Chapter 15 Surface Area and Volume In Text Exercise will help you. If you have any query regarding Rajasthan Board RBSE Class 8 Maths Chapter 15 Surface Area and Volume In Text Exercise, drop a comment below and we will get back to you at the earliest.