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PLEASE HELP ME I DONT HAVE A LONG TIME ):

The lateral area of a cone is 574 Pi Cm^2. The radius is 19.6 cm. What is the slant height to the nearest tenth of a centimeter?
9.3 cm
29.9 cm
42.5 cm
92.0 cm

User Tishma
by
7.1k points

2 Answers

3 votes
The correct answer is B) 29.9cm
User Marilena
by
6.9k points
5 votes

Answer:

Explanation:

Given that,

Lateral area of cone is 574π cm²

A = 574π cm²

Radius of the cone is 19.6cm

r = 19.6cm

What is the slant height

L =?

The lateral surface area of a cone is the area of the lateral or side surface only. So, the lateral area is the curved surface area.

So, curved surface area of a cone is given by.

A = πrL

Where

A is the area of the curved surfacer is the radius of the circle

L is the required slant height

π is a constant

A = πrL

574π = π×19.6×L

574π = 19.6πL

Then, divide both side by 19.6π

L = 574π / 19.6π

L = 29.2857cm

So, to the nearest tenth, nearest tenth means to 1d.p

L = 29.3cm.

The answer is not in the given option but I believe it should be the first option.

User VinSmile
by
6.5k points
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