Find the surface area of a sphere of radius 10.5 cm? Option 1: 1386 cm^2 Option 2: 1248 cm^2 Option 3: 4851 cm^2 Option 4: 1224 cm^2

Answer: 1386 cm^2. Solution: Surface area = 4 r^2 = 4 x 22/7 x (10.5)^2. (10.5)^2 = 110.25, and 22/7 x 110.25 = 346.5. So the area is 4 x 346.5 = 1386 cm^2.

Geometry

Solids

Easy

Find the surface area of a sphere of radius 10.5 cm?

1386 cm $^2$

1248 cm $^2$

4851 cm $^2$

1224 cm $^2$

✅ Correct Option: 1

Surface area $= 4\pi r^2 = 4 \times \dfrac{22}{7} \times (10.5)^2$ .

$(10.5)^2 = 110.25$ , and $\dfrac{22}{7} \times 110.25 = 346.5$ .

So the area is $4 \times 346.5 = 1386$ cm $^2$ .

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Solution

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