RS Aggarwal 2019,2020 solution class 7 chapter 19 Three Dimensional Shapes Exercise 19

Exercise 19

Page-224

Question 1:

Fill in the blanks:

(i) A cuboid has ...... rectangular faces ...... edges and ...... vertices.
(ii) A cylinder has ...... curved face and ...... flat faces.
(iii) A cone has one ...... face and one ...... face.
(iv) A sphere has a ...... surface.

Answer 1:

(i) A cuboid has 6 rectangular faces, 12 edges and 8 vertices.
(ii) A cylinder has 1 curved face and 2 flat faces.
(iii) A cone has one curved face and one flat face.
(iv) A sphere has a curved surface.

Question 2:

Write (T) for true and (F) for false:

(i) A cylinder has no vertex.
(ii) A cube has 6 faces, 12 edges and 8 vertics.
(iii) A cone has one vertex.
(iv) A sphere has one edge.
(v) A sphere has a curved surface.

Answer 2:

(i) True

(ii) True

(iii) True

(iv) False

(v) True

Question 3:

Write five examples of each one of (i) a cone (ii) a sphere (iii) a cuboid and (iv) a cylinder.

Answer 3:

(i) Conical Flask, Funnel, Ice Cream, Birthday Cap, Top
(ii) Cricket Ball, Foot Ball, Orange, Earth, Sun
(iii) Brick, Book, Eraser, Chocolate Bar, Mobile Phone
(iv) Circular Pipe, Gas Cylinder, Round Water Bottle, Mercury Tube, Pen