Answer:
Surface area is 288π cm² (exact solution), which is approximately 904.78 cm² (if you use pi on calculator) or 904.32 cm² (if you use 3.14 for pi).
Step-by-step explanation:
Surface area of cylinder
[tex]SA = 2 \times \text{area of base} + \text{lateral area}\\SA = 2 \pi r^2 + 2 \pi r h[/tex]
SA ... surface area
r ... radius
h ... height of cylinder
Given:
d = 12 cm
h = 18 cm
Since diameter d is 12 cm, that means that radius is half of that, so 6 cm.
r = 6 cm
Insert in formula:
[tex]SA = 2 \pi r^2 + 2 \pi r h\\SA = 2 \pi (6)^2 + 2 \pi (6)(18)\\SA = 72 \pi + 216 \pi\\SA = 288 \pi \text{ cm}^2 \approx 904.78 \text{ cm}^2[/tex]
