Question

Find the curved surface area and total surface area of a right circular cylinder
whose height is 15 cm and the radius of the base is 7 cm.​.
plz mark me BRAINLEAST

Answer 1

Given :

• Radius of the base , r = 7 cm
• Height ,h = 15 cm

To Find :

• Curved surface area
• And Total surface area

Formula's :

$\sf1)Total\:Surface\:Area=2\pi\:rh$

$\sf2)Curved\:Surface\:Area=2\pi\:r(r+h)$

Solution :

We have to find Curved surface area & Total surface area of the cylinder.

We know that

Curved surface Area = 2πrh

$\sf\implies\:CSA=2\times\dfrac{22}{7}\times7\times15$

$\sf\implies\:CSA=2\times22\times15$

$\sf\implies\:CSA=44\times15$

$\sf\implies\:CSA=660cm^2$

Therefore , The curved surface area of cylinder is 660 cm².

Now , Total surface area of the cylinder

$\sf=2\times\dfrac{22}{7}\times7(7+15)$

$\sf=2\times\dfrac{22}{7}\times7\times22$

$\sf=2\times22\times22$

$\sf=2\times484$

$\sf=968cm^2$

Therefore , The curved surface area of cylinder is 968 cm².

Answer 2

Answer:

⠀⠀⠀⌬ Height = 15 cm

⠀⠀⠀⌬ Radius = 7 cm

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$\underline{\bigstar\:\textsf{Curved Surface Area of cylinder :}}$

$:\implies\sf CSA=2\pi rh\\\\\\:\implies\sf CSA = 2 \times \frac{22}{7} \times 7 \times 15\\\\\\:\implies\sf CSA = 2 \times 22 \times 15\\\\\\:\implies\sf CSA = 660 \:cm^{2}$

⠀

$\therefore\:\underline{\textsf{Curved Surface Area of cylinder is \textbf{660 cm ^\text2 }}}.$

$\rule{200}{1}$

$\underline{\bigstar\:\textsf{Total Surface Area of cylinder :}}$

$:\implies\sf TSA=2\pi rh+2\pi r^2\\\\\\:\implies\sf TSA=2\pi r(h+r)\\\\\\:\implies\sf TSA = 2 \times \dfrac{22}{7} \times 7 \times (15 + 7)\\\\\\:\implies\sf TSA = 2 \times 22 \times 22\\\\\\:\implies\sf TSA = 968 \:cm ^{2}$

⠀

$\therefore\:\underline{\textsf{Total Surface Area of cylinder is \textbf{968 cm ^\text2 }.}}$