## Selina Concise Class 9 Maths Chapter 20 Area and Perimeter Of A Plane Figures Exercise 20C Solutions

Selina Concise Class 9 Maths Chapter 20 Area and Perimeter Of A Plane Figures Exercise 20C Solutions EXERCISE – 20C (1) The diameter of a circle is 28 cm. Find it’s (i) Circumference (ii) Area Solution: Given: Diameter = 28cm. ∴ radius = diameter/2 = 28/2 (r) radius = 14 Cm. (i) Circumference = 2 […]

## Selina Concise Class 9 Maths Chapter 20 Area and Perimeter Of A Plane Figures Exercise 20B Solutions

Selina Concise Class 9 Maths Chapter 20 Area and Perimeter Of A Plane Figures Exercise 20B Solutions Exercise 20B (1) Find the area of a quadrilateral one of whose diagonals is 30 cm. long and the Perpendiculars from the other two vertices are 19 cm and 11 cm respectively. Solution: Area (ABCD) = area (△ […]

## Selina Concise Class 9 Maths Chapter 19 Mean and Median Exercise 19C Solutions

Selina Concise Class 9 Maths Chapter 19 Mean and Median Exercise 19C Solutions Exercise 19C (1) Find the mean of 8, 12, 16, 22 and 4. Find the resulting if each of the observations. given above be: (i) multiplied by 3 (ii) Divided by 2 (iii) multiplied by 3 and then divides by 2 (iv) […]

## Selina Concise Class 9 Maths Chapter 19 Mean and Median Exercise 19B Solutions

Selina Concise Class 9 Maths Chapter 19 Mean and Median Exercise 19B Solutions EXERCISE – 19B (1) Find the median of: (i) 25, 16, 26, 16, 32, 31, 19, 28 and 35 Solution: First we will arrange given numbers in ascending order 16, 16, 19, 25, 26, 28, 31, 32 and 35 Total numbers are […]

## Selina Concise Class 9 Maths Chapter 19 Mean and Median Exercise 19A Solutions

Selina Concise Class 9 Maths Chapter 19 Mean and Median Exercise 19A Solutions EXERCISE – 19A (1) Find the mean of 43, 51, 50, 57 and 54. Solution: Given Number are = 43, 51, 50, 57 and 54. Mean x̄ = 43 + 51 + 50 + 57 + 54/ 5 = 255/5 x̄ = […]

## Selina Concise Class 9 Maths Chapter 13 Pythagoras Theorem Exercise 13B Solutions

Selina Concise Class 9 Maths Chapter 13 Pythagoras Theorem Exercise 13B Solutions EXERCISE – 13B (1) In the figure, given below, AD parallel to BC. Prove that c2 = a2 + b2 – 2ax. => To prove : c2 = a2 + b2 – 2ax Proof: In △ ADB, by Pythagoras theorem, (hypotenuse)2 = (Base)2 […]

## Selina Concise Class 9 Maths Chapter 13 Pythagoras Theorem Exercise 13A Solutions

Selina Concise Class 9 Maths Chapter 13 Pythagoras Theorem Exercise 13A Solutions EXERCISE – 13A (1) A ladder 13m long rests against a vertical wall if the foot of the ladder is 5m from the foot of the wall, find the distance of the other end of the ladder from the ground. => Given : […]

## Selina Concise Class 9 Maths Chapter 8 Logarithms Exercise 8D Solutions

Selina Concise Class 9 Maths Chapter 8 Logarithms Exercise 8D Solutions EXERCISE – 8D (1.) If 3/2 log a + 2/3 log b – 1 = 0, find the value of a9 b4. Solution : 3/2 log a + 2/3 log b – 1 = 0 3/2 log a + 2/3 log b = 1 […]

## Selina Concise Class 9 Maths Chapter 8 Logarithms Exercise 8C Solutions

Selina Concise Class 9 Maths Chapter 8 Logarithms Exercise 8C Solutions EXERCISE – 8C (1) If log10 8 = 0.90, find the value of : (i) log10 4 Solution : log10 8 = 0.90 log10 23 = 0.90 3 log10 2 = 0.90 log10 2 = 0.90/3 log10 2 = 0.30   (i) log10 4 […]

## Selina Concise Class 9 Maths Chapter 8 Logarithms Exercise 8B Solutions

Selina Concise Class 9 Maths Chapter 8 Logarithms Exercise 8B Solutions EXERCISE – 8B   (1) Express in terms of log2 and log 3 : (i) log 36 Solution : log 36 log (2×2×3×3) log (22 ×32) log22 + log32   {∵ log (a×b) = log a + log b} 2 log2 + 3 log3   […]