Page 1 - Home Assignment-3- Ch-13 SA and Volume(Cone)
P. 1

SAI International School
                                                     CLASS - IX

               Mathematics
               CHAPTER-13: SURFACE AREAS AND VOLUMES

               HOME ASSIGNMENT-3 [CONE]
               1.    The curved surface area of a cone is 4070       and diameter is 70 cm. What is its
                                                                      2
                     slant height?
               2.    Find the total surface area of a cone, if its slant height is 21 m and diameter of its
                     base is 24 m.
               3.
                     There are two cones, the curved surface area of one is twice that of the other. The
                     slant height of the later is twice that of the former. Find the ratio of their radii.
               4.
                     Find the ratio of the curved surface area of two cones, if their diameter of the bases
                     are equal and slant heights are in the ratio 4: 3.

               5.    Curved surface area of a cone is 308 cm  and its slant height is 14 cm. Find the
                                                                2
                     radius of the base and total surface area of the cone.
                     .
               6.    What length of tarpaulin 3 m wide will be required to make conical tent of height 8 m
                     and base radius 6 m? Assume that the extra length of material that will be required
                     for stitching margins and wastage in cutting is approximately 20 cm (Use π = 3.14).
               7.    The radius and height of a right circular cone are in the ratio of 5 : 12 and its volume
                     is 2512 cm . Find the slant height and radius of the base of the cone.
                                 3
                     (Take π = 3.14)

                                                                                            2
               8.    A conical tent is to accommodate 11 persons. Each must have 4 m  of the space on
                                           3
                     the ground and 20 m  air to breadth. Find the height of the tent.

               9.    A toy is in the form of a cone mounted on a hemisphere of base radius 3.5 cm. If the
                                                                                                        22
                     total height of e toy is 15. 5 cm. Find its total surface area of the toy [ Use π =    ]
                                                                                                        7
               10.  A cylindrical tent has a conical top with dimension as shown in the figure. Calculate
                     the total cost of the canvas required to make the tent, if the cost of canvas is Rs 50
                           2
                     per m .















                                                            1
   1   2   3