Question

a toy is in form of a cone surmounted on a hemisphere of same radius 3.5cm. the total height of the toy is 15.5cm find total surface area of the toy

Answer 1

therefore answer is 214.5cm sq

Answer 2

Answer:

Total surface area of the toy = 251.5611 square cm.

Step-by-step explanation:

Given : A toy is in form of a cone surmounted on a hemisphere of same radius 3.5cm. the total height of the toy is 15.5cm

To find : Total surface area of the toy.

Solution :

Radius given is r=3.5 cm

Height h=15.5 cm

Total surface area of the toy = CSA of cone + CSA of hemisphere

CSA of hemisphere is $H=2\pi r^{2}$

$H=2(3.14)(3.5)^{2}$

$H=2(3.14)(3.5)^{2}$

$H=2(3.14)(12.25)$

$H=76.93cm^2$

CSA of cone is $C=\pi \times r\times l$

where l is slant height given by

$l=\sqrt{h^2+r^2}$

$l=\sqrt{15.5^2+3.5^2}$

$l=\sqrt{240.25+12.25}$

$l=\sqrt{252.5}$

$l=15.89$

$C=\pi \times r\times l$

$C=3.14 \times 3.5\times 15.89$

$C=174.6311cm^2$

Total surface area of the toy = CSA of cone + CSA of hemisphere

Total surface area of the toy = 174.6311 + 76.93

Total surface area of the toy = 251.5611 square cm.