Chapter 11 Mensuration Exercise 11.2
Chapter 11 Mensuration Exercise 11.2 Question 1. The shape of the top surface of a table is a trapezium. Find its area if its parallel sides are 1 m and 1.2 m and perpendicular distance between them is 0.8 m. Solution: Question 3. Length of the fence of a trapezium-shaped field ABCD is 120 m. […]
Chapter 11 Mensuration Exercise 11.1
Chapter 11 Mensuration Exercise 11.1 Question 1. A square and a rectangular field with measurements as given in the figure have the same perimeter. Which field has a larger area? Solution: Perimeter of figure (a) = 4 × side = 4 × 60 = 240 m Perimeter of figure (b) = 2 [l + b] […]
Chapter 10 Visualising Solid Shapes
Chapter 10 Visualising Solid Shapes Very Short Answer Type Question 1. Draw any four 3-dimensional figures. Solution: Question 2. Verify Euler’s formula for a right triangular prism. Solution: Number of vertices (V) = 6 Number of faces (F) = 5 and number of edges (E) = 9 Euler’s formula: V + F – E = […]
Chapter 10 Visualising Solid Shapes Exercise 10.3
Chapter 10 Visualising Solid Shapes Exercise 10.3 Question 1. Can a polyhedron have for its faces (i) 3 triangles? (ii) 4 triangles? (iii) a square and four triangles? Solution: (i) No, because polyhedron must have edges meeting at vertices which are points. (ii) Yes, because all the edges are meeting at the vertices. (iii) Yes, […]
Chapter 10 Visualising Solid Shapes Exercise 10.2
Chapter 10 Visualising Solid Shapes Exercise 10.2 Question 1. Look at the given map of a city. Answer the following. (a) Colour the map as follows: Blue-water, red- fire station, orange-library, yellow-schools, Green-park, Pink-College, Purple-Hospital, Brown-Cemetery. (b) Mark a green ‘X’ at the intersection of Road ‘C’ and Nehru Road, Green ‘Y’ at the intersection […]
Chapter 10 Visualising Solid Shapes Exercise 10.1
Chapter 10 Visualising Solid Shapes Exercise 10.1 Question 1. For each of the given solid, the two views are given. Match for each solid the corresponding top and front views. The first one is done for you. Solution: (a) A bottle → (iii) → (iv) (b) A weight → (i) → (v) (c) A flask […]
Chapter 9 Algebraic Expressions and Identities
Chapter 9 Algebraic Expressions and Identities Very Short Answer Type Question 1. Write two examples of each of (i) Monomials (ii) Binomials (iii) Trinomials Solution: (i) Monomials: (a) 3x (b) 5xy2 (ii) Binomials: (a) p + q (b) -5a + 2b (iii) Trinomials: (a) a + b + c (b) x2 + x + 2 Question […]
Chapter 9 Algebraic Expressions and Identities Exercise 9.5
Chapter 9 Algebraic Expressions and Identities Exercise 9.5 Question 1. Use a suitable identity to get each of the following products: Solution: Question 2. Use the identity (x + a)(x + b) = x2 + (a + b)x + ab to find the following products. (i) (x + 3) (x + 7) (ii) (4x + 5)(4x […]
Chapter 9 Algebraic Expressions and Identities Exercise 9.4
Chapter 9 Algebraic Expressions and Identities Exercise 9.4 Solution: (i) (2x + 5) × (4x – 3) = 2x × (4x – 3) + 5 × (4x – 3) = (2x × 4x) – (3 × 2x) + (5 × 4x) – (5 × 3) = 8×2 – 6x + 20x – 15 = 8×2 + 14x […]
Chapter 9 Algebraic Expressions and Identities Exercise 9.3
Chapter 9 Algebraic Expressions and Identities Exercise 9.3 Question 1. Carry out the multiplication of the expressions in each of the following pairs: (i) 4p, q + r (ii) ab, a – b (iii) a + b, 7a2b2 (iv) a2 – 9, 4a (v) pq + qr + rp, 0 Solution: (i) 4p × (q + […]