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adell [148]
3 years ago
11

Help I be trying so but can figure out the answer

Mathematics
2 answers:
Ede4ka [16]3 years ago
8 0

Answer:

Step-by-step explanation:

We are to assume the earth is a sphere and the radius has been given in the question which is 3959 miles

Area of a sphere = 4*pi*r^2

Where pi= 22/7 (constant)

r= radius

Area= 4*22/7*3959^2

=4*22/7*15673681

=1379283928/7

=197040561.14 square mile

=197040561.14 mi^2

Total area of the earth has been solved as 197040561.14 mi^2 and 20 percent of this surface area is suitable to live on.

We calculate the 20% thus:

20/100 * 197040561.14 mi^2

=3940811222.8/100 mi^2

=39408112.228mi^2

There are approximately 7.7 billion people on earth that will live on the suitable land with an area of 39408112.228mi^2

Each person in the world will have square mile of

39408112. 228 mi^2 / 7.7billion persons

=39408112.228/7700000000

=0.0051179367mi^2 per person

Approximately, 0.00512mi^2/person (option C)

Check the attachment for better mathematical expressions

Sphinxa [80]3 years ago
4 0

Answer:

b

Step-by-step explanation:

Surface of the earth =3959×3.14

=12,437.565

if 20%is suitable so we multiply it by the surface

12,437.565×0.2=2,487.513 per people

2,487.513/7,700,00,00

So I think it will be the closest to b

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