Everything Maths Grade 10

4 cm

14 cm

h

h^2 = 4^2 + 14^2

)h=

√

42 + 14^2

= 2

p

53 cm

area of walls=

1

2

2 rh

=(4)

(

2

p

53

)

= 8

p

53 cm^2

Step 3: Find the sum of the areas

total surface area= 16+ 8

p

53

=233,2 cm^2

Step 4: Write the final answer

The surface area of the cone is 233,2 cm^2.

Worked example 10: Finding the surface area of a sphere

QUESTION

Find the surface area of the following sphere (correct to 1 decimal place):

5 cm

436 13.3. Right pyramids, right cones and spheres