The radius and height of a cylinder are in the ratio 2 : 1 find its total surface area if curved surface area is 616 m².

Correct option is B

Given: 

Radius : Height = 2 : 1,

Curved Surface Area = $$616 \, \text{m}^2$$​

Formula Used:

$$CSA = 2\pi rh, \\ \ \\ \text{Total Surface Area (TSA): } \ \ 2\pi r(r + h)$$​

Solution: 

Let h = a then r = 2a  put in curved surface are: 

then, 

​$$616 = 2\pi. 2a . a$$​​

616 = 2 $$\times$$​ 3.14 $$\times$$​ 2 $$\times$$​ a²​

a = 7 

then,

$$r = 14, h = 7 \\ \ \\ \text{Now, Total surface area} ; , \\ \ \\ \text{TSA = } 2\pi \times 14 \times (14 + 7) \approx 1848 \, \text{m}^2$$

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