Question

Assuming the earth to be a sphere of radius 6370 km, how many square kilometres is area of the land, if three-fourth of the earth’s surface is covered by water?

Answer 1

Answer:

The Area of earth land is 127411466 km

Step-by-step explanation:

Given as :

The radius of earth of sphere shaped = r = 6370 km

∵ volume of sphere = $\dfrac{4}{3}$ × π × r³

Or, volume of earth = volume of sphere = $\dfrac{4}{3}$ × 3.14 × 6370³

∴ volume of earth = 1.0821 × $10^{12}$

And Total surface area of earth = total surface area of sphere = 4 × π × r²

i.e TSA = 4 × 3.14 × 40576900

Or, TSA = 509645864 sq km

Now, $\dfrac{3}{4}$ th of earth cover with water

So, The part of earth land = 1 - $\dfrac{3}{4}$  = $\dfrac{1}{4}$

So, Area of earth land = 509645864 sq km × $\dfrac{1}{4}$

Hence, The Area of earth land is 127411466 km Answer

Answer 2

Answer:

The Area of earth land is 127411466 km

Step-by-step explanation:

Given as :

The radius of earth of sphere shaped = r = 6370 km

∵ volume of sphere = \dfrac{4}{3}

3

4

× π × r³

Or, volume of earth = volume of sphere = \dfrac{4}{3}

3

4

× 3.14 × 6370³

∴ volume of earth = 1.0821 × 10^{12}10

12

And Total surface area of earth = total surface area of sphere = 4 × π × r²

i.e TSA = 4 × 3.14 × 40576900

Or, TSA = 509645864 sq km

Now, \dfrac{3}{4}

4

3

th of earth cover with water

So, The part of earth land = 1 - \dfrac{3}{4}

4

3

= \dfrac{1}{4}

4

1

So, Area of earth land = 509645864 sq km × \dfrac{1}{4}

4

1

Hence, The Area of earth land is 127411466 km