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2 years ago

A solid shape is made by joining two cones.

Mathematics

1 answer:

dlinn [17]2 years ago

3 0

The surface area of the solid shape is the amount of space on it

The radius of the two cones is 2.93 cm

<h3>How to determine the radius?</h3>

The given parameters are:

Cone 1: slant height, l = 2r
Cone 2: slant height, L = 3r
Surface area = 135. 21 cm²

The surface area of the shape is calculated using:

T = πr(L + l)

So, we have:

135.21 = πr(2r + 3r)

Evaluate

135.21 = 5πr²

Divide both sides by 5π

r² = 135.21/5π

Evaluate the quotient

r² = 8.61

Take the square root of both sides

r = 2.93

Hence, the radius of the cones is 2.93 cm

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