mple 1 : Rasheed got a playing top (laitu) as hisbirthday present, which surprisingly had no colour onit. He wanted to colour it with his crayons. The top is 5crmshaped like a cone surmounted by a hemispheresee Fig 13.6). The entire top is 5 cm in height andthe diameter of the top is 3.5 cm. Find the area he3.5 cmCEuLhas to Colour. (Take Ď--)Fig. 13.6

mple 1 : Rasheed got a playing top (laitu) as hisbirthday present, whi

1.	mple 1 : Rasheed got a playing top (laitu) as hisbirthday present, which surprisingly had no colour onit. He wanted to colour it with his crayons. The top is 5crmshaped like a cone surmounted by a hemispheresee Fig 13.6). The entire top is 5 cm in height andthe diameter of the top is 3.5 cm. Find the area he3.5 cmCEuLhas to Colour. (Take Ď--)Fig. 13.6
Answer» Given:Height of the top= 5cmDiameter of the top= 3.5 cmTo find: Area Solution:Radius=r=3.5/2Surface area of hemisphere=2 phi r^2=2(22/7)(3.5/2)^2=19.25cm2Curved surface area of cone= phirlheight of cone= height of top-radius of hemisphere=5-1.75=3.25cmhere l^2=h^2+ r^2l^2=(3.25)^2+(1.75)^2i^2=13.6225l=3.68cmcurved surface area of cone= phirl22/7 3.5/2 3.6=19.8cm2thereforesurface area of top= surface area of hemisphere + curved surface area of cone= 19.25+ 19.8=39.05Answer: area of top= 39.05cm2