Ashleeds07
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Juan wants to know the cross-sectional area of a circular pipe. He measures the diameter which he finds, to the nearest millimeter, to be 5 centimeters.


To find the area of the circle, Juan uses the formula A=2〖πr〗^2 where A is the area of the circle and r is its radius. He uses 3.14 for π. What value does Juan get for the area of the circle? Make sure you include your units.

Michelle found the area of a circle as 78.5 〖in〗^2. She used 3.14 for π. What is the radius of the circle? Explain how you found your answer.

(Help please)

Respuesta :

Step-by-step explanation:

Juan wants to know the cross-sectional area of a circular pipe. He measures the diameter which he finds, to the nearest millimetre, to be 5 centimetres

It means radius is 2.5 cm. For the area of circle he gets the formula as :

[tex]A=\pi r^2\\\\A=3.14\times (2.5)^2\\\\A=19.62\ cm^2[/tex]

If Michelle found the area of a circle as [tex]A=78.5\ in^2[/tex]

So,

[tex]A=\pi r^2\\\\r=\sqrt{\dfrac{A}{\pi}} \\\\r=\sqrt{\dfrac{78.5}{3.14}} \\\\r=5\ \text{inch}[/tex]

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