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A right cone has a radius 3 and slant height 5. the radius and slant height are both multiplied by 3/2. describe the effect on the surface area



User Rhamel
by
3.2k points

2 Answers

1 vote

First lets find the surface area of cone without effect

Given:

Radius of cone = 3 units

Slant height of cone = 5 units

To find:

Surface area of cone

Steps:

Surface area of a cone = πr (r + l)

= π × 3(3 + 5)

= π × 3 (8)

= π × 24

= 24π unit²

Now lets find the surface area of cone with effect

Given:

Radius of cone = 3 × 3/2 = 9/2 = 4.5 units

Slant height of cone = 5 × 3/2 = 15/2 = 7.5 units

To find:

Surface area of cone

Steps:

surface area of cone = πr(r + l)

= π × 4.5( 4.5 + 7.5 )

= π × 4.5( 12 )

= π × 54.0

= 54π

Since we know the surface area of the cones before and after affect now lets find effect

Given:

Surface area of cone before affect = 24π

Surface area of cone after affect = 54π

To find:

Effect on the surface area of cone before and after change

Steps:

By dividing the surface area of cone after and before affect will give us the effect on the cone

54π / 24π

= 54/24 (pi gets canceled out)

= 27/12

= 2.25

Therefore the area of cone is multiplied by 2.25 after effect.

Happy to help :)

If you need any help, please feel free to ask.

User Enticedwanderer
by
3.3k points
1 vote

Answer:

The surface area is multiplied by 4/9.

Explanation:

you welcomeeeeeeeeeeeeeeeeeeeeeeeee

User Pawel Gumiela
by
3.9k points