Answer :

The surface area of the cylinder = lateral area + 2 base area

Since the surface area = 325 in^2

Since the lateral area = 200 in^2

Subtract them to find 2 base area

2 base area = 325 - 200 = 125

Divide it by 2 to find the base area

[tex]\begin{gathered} b\mathrm{}A=\frac{125}{2} \\ b\mathrm{}A=62.5 \end{gathered}[/tex]

Since the base of the cylinder is a circle

Since the area of the circle is

[tex]b\mathrm{}A=\pi\times r^2[/tex]

Substitute bA by 62.5

[tex]62.5=\pi\times r^2[/tex]

Divide both sides by pi

[tex]\frac{62.5}{\pi}=r^2[/tex]

Take a square root for both sides

[tex]\begin{gathered} \sqrt[]{\frac{62.5}{\pi}}=r \\ r=4.46031092 \end{gathered}[/tex]

Round it to the nearest tenth

r = 4.5 inches

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