Question

Find the radius of sphere whose surface area is 154cm square

Answer 1

r²=154 x 7 / 22 x 4
   r = 3.5 cm

Answer 2

Given :

• Surface Area of Sphere = 154cm²

To Find :

• Radius of Sphere.

Solution :

$\longrightarrow\tt{Surface\:Area=154{cm}^{2}}$

Using Formula :

$\boxed{Surface\:Area\:of\:Sphere=4\pi{{r}^{2}}}$

Putting Values :

$\longrightarrow\tt{154=4\times\dfrac{22}{7}\times{{r}^{2}}}$

$\longrightarrow\tt{154\times{7}=22\times{4}\times{{r}^{2}}}$

$\longrightarrow\tt{1078=88{r}^{2}}$

$\longrightarrow\tt{\cancel\dfrac{1078}{88}={r}^{2}}$

$\longrightarrow\tt{\sqrt{12.25}={r}^{2}}$

$\longrightarrow\tt\bold{r=3.5cm}$

So , The Radius of Sphere is 3.5cm...

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• Surface Area of Sphere = 4πr²
• Volume of Sphere = 4/3πr³

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