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10 votes
10 votes
3. The volume of the cone is 4π dm3 and the diameter of the base is 80 cm. Calculate the cone: the area of the base.

User Jensengar
by
3.2k points

1 Answer

22 votes
22 votes

Answer:


Area\text{ of the base = 50.24 dm}^2

Step-by-step explanation:

Given:

Volume of the cone = 4π dm³

diameter of the base = 80cm

To find:

the area of the base

The base of a cone is a circle. Area of the base will be area of the circle


\begin{gathered} Area\text{ of a circle = \pi r}^2 \\ r\text{ = radius} \end{gathered}

diameter = 80cm

diameter = 2(radius)

radius = diameter/2

radius = 80/2 = 40 cm

We need to convert from cm to dm to get same units

10cm = 1 dm

40cm = 4 dm

let π = 3.14

substitute the values into the formula:


\begin{gathered} Area\text{ of the circle = 3.14 }*\text{ 4}^2 \\ Area\text{ of the circle = 50.24} \\ \\ Area\text{ of the base = 50.24 dm}^2 \end{gathered}

User Christoph Kempen
by
2.9k points
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