#### Chapters

Chapter 2: Parallel lines and transversals

Chapter 3: Indices and Cube root

Chapter 4: Altitudes and Medians of a triangle

Chapter 5: Expansion formulae

Chapter 6: Factorisation of Algebraic expressions

Chapter 7: Variation

Chapter 8: Quadrilateral : Constructions and Types

Chapter 9: Discount and Commission

Chapter 10: Division of Polynomials

Chapter 11: Statistics

Chapter 12: Equations in one variable

Chapter 13: Congruence of triangles

Chapter 14: Compound interest

Chapter 15: Area

Chapter 16: Surface area and Volume

Chapter 17: Circle : Chord and Arc

#### Balbharati Balbharati Class 8 Mathematics

## Chapter 7: Variation

#### Chapter 7: Variation Exercise Practice Set 7.1 solutions [Pages 36 - 37]

Write the following statement using the symbol of variation.

Circumference (c) of a circle is directly proportional to its radius (r).

Write the following statement using the symbol of variation.

Consumption of petrol (l) in a car and distance travelled by that car (d) are in direct variation.

Complete the following table considering that the cost of apples and their number are in direct variation.

Number of apples (x) | 1 | 4 | ... | 12 | ... |

Cost of apples (y) | 8 | 32 | 56 | ... | 160 |

If m ∝ n and when m = 154, n = 7. Find the value of m, when n = 14

If n varies directly as m, complete the following table.

m | 3 | 5 | 6.5 | ... | 1.25 |

n | 12 | 20 | ... | 28 | ... |

y varies directly as square root of x. When x = 16, y = 24. Find the constant of variation and equation of variation.

The total remuneration paid to labourers, employed to harvest soyabeen is in direct variation with the number of labourers. If remuneration of 4 labourers is ₹ 1000, find the remuneration of 17 labourers.

#### Chapter 7: Variation Exercise Practice Set 7.2 solutions [Pages 38 - 40]

The information about numbers of workers and number of days to complete a work is given in the following table. Complete the table.

Number of workers | 30 | 20 | 10 | ||

Days | 6 | 9 | 12 | 36 |

Find constant of variation and write equation of variation for every example given below.

p ∝ \[\frac{1}{q}\] ; if p = 15 then q = 4

Find constant of variation and write equation of variation for every example given below.

z ∝ \[\frac{1}{w}\] ; when z = 2.5 then w = 24

Find constant of variation and write equation of variation for every example given below.

s ∝ \[\frac{1}{t^2}\] ; if s = 4 then t = 5

Find constant of variation and write equation of variation for every example given below.

x ∝ \[\frac{1}{\sqrt{y}}\] ; if x = 15 then y = 9

The boxes are to be filled with apples in a heap. If 24 apples are put in a box then 27 boxes are needed. If 36 apples are filled in a box how many boxes will be needed?

Write the following statement using symbol of variation .

The wavelength of sound (l) and its frequency (f) are in inverse variation.

Write the following statement using symbol of variation .

The intensity (I) of light varies inversely with the square of the distance (d) of a screen from the lamp.

x ∝ \[\frac{1}{\sqrt{y}}\] and when x = 40 then y = 16. If x = 10, find y.

x varies inversely as y, when x = 15 then y = 10, if x = 20 then y = ?.

#### Chapter 7: Variation Exercise Practice Set 7.3 solutions [Page 40]

Which of the following statement is of inverse variation?

Number of workers on a job and time taken by them to complete the job.

Which of the following statement is of inverse variation?

Number of pipes of same size to fill a tank and the time taken by them to fill the tank.

Which of the following statement is of inverse variation?

Petrol filled in the tank of a vehical and its cost

Which of the following statement is of inverse variation?

Area of circle and its radius.

If 15 workers can build a wall in 48 hours, how many workers will be required to do the same work in 30 hours ?

120 bags of half litre milk can be filled by a machine within 3 minutes find the time to fill such 1800 bags ?

A car with speed 60 km/hr takes 8 hours to travel some distance. What should be the increase in the speed if the same distance is to be covered in 7\[\frac{1}{2}\] hours?

## Chapter 7: Variation

#### Balbharati Balbharati Class 8 Mathematics

#### Textbook solutions for Class 8

## Balbharati solutions for Class 8 Mathematics chapter 7 - Variation

Balbharati solutions for Class 8 chapter 7 (Variation) include all questions with solution and detail explanation. This will clear students doubts about any question and improve application skills while preparing for board exams. The detailed, step-by-step solutions will help you understand the concepts better and clear your confusions, if any. Shaalaa.com has the Maharashtra State Board Balbharati Class 8 Mathematics solutions in a manner that help students grasp basic concepts better and faster.

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Concepts covered in Class 8 Mathematics chapter 7 Variation are Direct Variation, Inverse Variation, Time, Work, Speed.

Using Balbharati Class 8 solutions Variation exercise by students are an easy way to prepare for the exams, as they involve solutions arranged chapter-wise also page wise. The questions involved in Balbharati Solutions are important questions that can be asked in the final exam. Maximum students of Maharashtra State Board Class 8 prefer Balbharati Textbook Solutions to score more in exam.

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